By at least one comprehensive measure of value, Ben Zobrist was the best player in baseball last year. Yes, by Wins Above Replacement (WAR), the FanGraphs statistic that includes component statistics from both the offensive and defensive side of the ball, Zobrist was worth 8.6 WAR last year as he rode solid defense at second base just barely past Albert Pujols.

It was, to say the least, a surprise. The year before, Zobrist had accumulated a mere 1.3 WAR in his 227 plate appearances. In fact, since FanGraphs started tracking the stat in 2002, Zobrist’s 2009 effort created the biggest gap between a player’s best season by WAR and his second-best season. Let’s check out the rest of the biggest “flukes.”

                   Best WAR   Second-Best WAR    Difference
Ben Zobrist         8.6          1.3             7.3
Adrian Beltre       9.9          4.6             5.3
Richard Hidalgo     6.1          1.8             4.3
Ryan Ludwick        5.7          1.9             3.8
Magglio Ordonez     8.8          5.2             3.6
J.D. Drew           8.3          4.8             3.5
Bret Boone          7.3          3.8             3.5
Jim Thome           7.3          4.8             2.5

Luckily for the Rays, Zobrist’s big season did not come in a contract year like it did for second place on this list, Adrian Beltre. If Zobrist falls back to a Beltre-like level of performance in the future, his 2009 will be seen as a fluke, no two ways about it. On the other hand, this list also shows that not all flukes are created equal. Yes, Beltre has a big gap between his best and second-best years, but his second-best WAR total was pretty good, too.

Richard Hidalgo and Bret Boone provide a cautionary tale for Zobrist as neither came close to repeating their top WAR seasons. In their defense, Hidalgo and Boone both had good pre-2002 years that could not factor into this analysis, so it’s possible the gap between their two best seasons is not quite this large. Ryan Ludwick may yet close his gap, but like Magglio Ordonez and J.D. Drew before him, he doesn’t have Zobrist’s solid infield defense (or positional versatility) to his credit.

Since 2002, the lowest second-best WAR for a player that accumulated 8+ WAR in one season was Beltre’s 4.6. If that’s the best Zobrist does in the future, he’ll still provide the Rays great value in the short-term. Only three second basemen in baseball bettered that number last year. But we should keep in mind the careers of Boone and Hidalgo before we assume Zobrist has established a new level of performance.

It’s time to look at last year’s rookies. Because the player caps for each of these players will provide you more in-depth detail than we can hope to provide in an overview, this article will attempt to quickly point out one or two pieces of evidence that might predict an improvement or a decline in the stats of the following 2009 rookies. Once you spot an opinion you don’t agree with, check the player capsule, the FanGraphs stats, and come join us at the website and the boards for what will surely be a lively discussion about the future of these (mostly) young players coming off their debut seasons.

National League

Tommy Hanson: Though his strand rate (80.3%) and BABIP (.280) could regress a little and provide him some problems, Hanson had serious strikeout ability (8.18 K/9) and his minor league numbers seem to suggest that even better performances are on the way. It helps that he plays in the inferior league and that his arm has been built up reasonably gently. Best bet: improve.

Andrew McCutchen: The wheels and the batting average are legit, and the only question is whether McCutchen will show the same pop in the future. True, his ISO last year (.185) bested every minor league seasons save one, but McCutchen put more balls into the air (39.1%) and over the fence (8.8%) than a pure speedster might. As his frame fills out, the power may prove legit. Best bet: improve.

Colby Rasmus: Last year Rasmus showed reasonable power (.156 ISO), but lacked the speed we saw in the minors (74 stolen bases, 81.3% success). Perhaps the speed won’t be as nice as we thought it would be, but Rasmus had legitimate full-season ISOs over .200 in the minor leagues, so the power is for real. With a little better luck on batted balls (.284 BABIP), Rasmus has the chance to put together a nice power/speed year in the mold of (less speedy) Grady Sizemore. Best bet: improve.

Chris Coghlan: Because of his luck with the batted ball (.366 BABIP) and his probable position eligibility change, Coghlan won’t provide the same batting-average burst for your infield in 2010. It’s also hard to glean his true power level, as his ISOs have ranged from last year’s mediocrity (.139 ISO) to something more powerful (.200+ ISOs in the minors) over his career. He didn’t steal efficiently last year, either (61.5% success rate), but was better in the minors (80%), so he could improve there. Best bet: about the same, but with only outfield eligibility for now.

Everth Cabrera: This infielder is fast (7.9 speed score) and has a limp noodle bat (.106 ISO) – that much we know. A player like this is useful when he can pair that combination with a strong batting average, which is the largest question in regards to the diminutive (5’10”, 176 lbs) former Rule-5 shortstop. His BABIP doesn’t point to a bounceback (.328), and his meager contact rate (81.9%) doesn’t point to a great batting average either. Best bet: about the same.

Alcides Escobar: Another speedy infielder, Escobar has some of the same skills, but a better contact rate (83.3%) and a history of better strikeout rates in the minor leagues than Cabrera (21% for Cabrera, 15.8% for Escobar). With sub-.100 ISOs in the minor leagues, Escobar won’t develop any power, but more help in the batting-average and stolen-base categories is a strong bet. Best bet: about the same, just more of it.

Dexter Fowler: Fowler showed the speed (27 stolen bases, 72.9% success) and some repeatable power (.141 ISO, .152 minor league ISO), but the thing that Fowler really needs to work on is his strikeout rate (26.8% in 2009). It’s a good thing that his minor league numbers (23.7%) seem to suggest he can cut the strikeouts. On the negative side, if the Rockies hold on to all of their outfielders, Fowler will have to fight for playing time. Best bet: about the same.

J.A. Happ: The luck stats are not kind to Happ. He stranded more runners than he should have (85.2%) and his BABIP was also not sustainable (.270). When those return to normal, his mediocre strikeout rate (6.69 K/9) won’t play as well. Perhaps he needs to throw his secondary pitches more because, had he qualified, he would have thrown his fastball ninth-most in the Majors last year (69.9%). Best bet: decline.

Randy Wells: It’s easy to root for the unheralded 27-year-old rookie, and some might get excited about his relatively neutral luck stats (.294 BABIP, 76% BABIP), but fundamentally, it’s important to retain your senses when it comes to a pitcher with a below-average strikeout rate (5.66 K/9). His good ground-ball rate (47.9%) might help explain his 3.88 FIP, but his xFIP (4.24) is a better predictor for his true ability. Best bet: decline.

Casey McGehee: Be suspicious. Be very suspicious. Not only did McGehee get a little lucky with the batted ball (.335 BABIP, .305 xBABIP), but he showed an ISO (.197) that was above and beyond the power he showed in the minor leagues (.130). Don’t pro-rate out that power in your projections next year, and don’t depend on the batting average to last. Best bet: decline.

Garrett Jones: Had he qualified, Jones’ 21.2% HR/FB percentage would have tied for eighth-best in the entire league (with Nelson Cruz) – this, despite a minor league ISO that was only okay (.192). Of course, Jones has been better more recently (.800+ OPS at his last three minor league stops), but you always have to be suspicious of older rookies – especially ones with a .327 BABIP and a career .258 batting average in the minor leagues. Best bet: decline.

American League

Brett Anderson: Perhaps because his ERA started with a four, many people didn’t notice how nice of a season this rookie had. He struck out 150 batters and paired that with only 45 walks in 175+ innings. He had a ground-ball rate more than 50%, and his FIP was 3.69 – all great numbers for a freshman. The even better news is that his strikeout rate, though okay in 2009 (7.70), has room for improvement when seen through the prism of his minor league strikeout rates (9.7). Make sure to take a look at his plus slider (+22.1 runs), because it’s a doozy. Best bet: improve.

Elvis Andrus: The Texas shortstop got more attention than his fellow rookie all-speed shortstops, and perhaps there is a reason for the excitement beyond the plus defense. His contact rate (87.3%) easily bested that of the shortstops in Milwaukee and San Diego, even if his ISO was equally weak (.106). With a reach rate (19.6%), strikeout rate (16%), and line-drive rate (21.9%) as reasonable as Andrus showed, it’s reasonable to think the speedster can add to his BABIP (.307) and improve his batting average next year. Best bet: improve.

Gordon Beckham: Beckham is already a solid player, as his walk rate (9.8%), strikeout rate (17.2%), and ISO (.190) can attest. If he can up his contact rate (80.1%) and his line-drive rate (16.6%), then the consistency and overall improvement that the projections seem to expect will come. Even if you “only” pro-rate out his stats from last year to a full year, you are talking about a 20/10 infielder with a passable batting average. With the acquisition of Teahen, you may even be talking about a dark-horse top-three second baseman next year. Best bet: improve.

Matt Wieters: A debut that had Wieters put forth the run production of an average Major Leaguer (101 wRC+) was considered a poor effort after some projections had him starting his career with a bang. Perhaps his ISO (.124) or walk rate (7.4%) were the most disappointing aspects of his game given his minor league numbers in those categories (.233 and 14.7% respectively). His .362/.425/.511 September lends some credibility to the generally held idea that he will move his numbers towards his stellar minor league level (1.014 minor league OPS). Best bet: improve.

Rick Porcello: Though there was a lot of support for Porcello’s ROY candidacy, his season was actually a mixed bag. The good included his ground-ball rate (54.2%, fifth best among qualified starters) and walk rate (2.74 BB/9). Though that’s a good foundation, Porcello may need to start throwing his secondary offerings a little more (77.1% fastball usage, second-most in the league) in order to improve his below-average strikeout rate (4.69 K/9). The ERA may look worse next year as some of his luck stats regress (.287 BABIP, 75.5% LOB), but the overall package should improve. Best bet: improve, though possibly only marginally.

Andrew Bailey: This ROY had such a great season that he’s probably likely to decline. His luck stats will regress some, for sure (.234 BABIP, 84.9% LOB). But there’s so much good in his bag of tricks (9.83 K/9, 2.59 BB/9) that even with some regression he’ll be a solid closer in 2010. Look at how often batters reach (27.4%) and how seldom they make contact outside the zone (56.4%) and you’ll see he has nasty stuff. Best bet: more of the same, even with a little regression.

Travis Snider: The story of Travis Snider is the story of striking out. So far in his short career (356 PAs), Snider has struck out in a whopping 32.2% of his plate appearances and given his contact rate so far (71%), he doesn’t look to be poised to change his whiffing ways. Even with that said, his athleticism alone should allow Snider to best his .241 batting average last year. His power is still strong (.175) and inching its way to his minor league heights (.229), so he has that going for him. He has the tools and the pedigree to back up his projections. Best bet: improve, even if the batting average won’t be stellar.

Julio Borbon: Ron Washington already declared center field and leadoff Borbon’s to lose during the spring training, and Marlon Byrd’s signing with the Cubs helped cement Borbon’s new, expanded role with the Rangers. He stole 19 bags in just 179 plate appearances last year, and that speed will be the reason you take a shot of Borbon in 2010. He’ll also be a good bet for a .300 average given his speed (6.3 speed score) and ability to make contact (86.2%). Best bet: improve.

Nolan Reimold: Already sporting nice power (.187 ISO) and some speed to boot (8/10 stolen base attempts), Reimold is one of the best outfield sleepers for the upcoming year. With a HR/FB percentage like he sported (14.2%), all he needs to do is get the ball in the air a little more (37.3% FB) to start racking up the home runs. He consistently showed more power in the minor leagues, and with his nice walk (11.6%) and strikeout rates (21.5%), there’s a lot of reason for excitement about this young man’s future. Best bet: improve.

Jeff Niemann: The good news about Niemann is that last season was not ostensibly a result of his luck. His BABIP (.304) and LOB% (73.7%) were both reasonable, and his 4.07 FIP reflected those facts. But the bad news is that many of his stats were just slightly above average (walk rate, home run rate) or slightly below average (strikeout rate, ground-ball percentage). His curveball and change-up were better-than-neutral pitches, so perhaps he should use them more often (71.9% fastball usage). Best bet: more of the same, even if some of the traditional statistics look less exciting.

Overall team outlook: Brian Sabean continues to run out declining and generally uninspiring veterans on offense, but since he was lucky enough to run into some serious starting pitching, his teams continue to be relevant late in the season. Is this the year a few of his veterans drink from the fountain of youth and score just enough runs to make it to the postseason?

The Starting Rotation: This is the rare starting rotation where every pitcher is rosterable in standard 12-team mixed fantasy leagues. Sure, Tim Lincecum and his incredible strikeout rate is the prize, but even all the way down to rookie Madison Bumgarner, the Giants’ staff offers something for everyone. Matt Cain may take a step back next year if his luck stats are to be trusted, but even with a slightly higher WHIP, he’ll be a solid mid-rotation fantasy starter.

Barry Zito has gone from laughing stock to afterthought to spot starter over the last three years. He plays enough games against the Padres to be interesting from time to time – and fantasy owners don’t have to pay his ridiculous salary. Jonathan Sanchez may actually be the most divisive Giants starter in fantasy circles – you either believe in his strikeouts, or you think the walks will keep him from ever fulfilling his potential.

The Bullpen: Beach Boy Brian Wilson made huge strides last year by increasing his strikeout rate and decreasing his walk rate. His luck stats don’t scream regression, but the projections have him taking a step back and losing some of those gains. No matter, he’ll still be a top closer, if only because he looks relatively stable, is young, and plays for a team that should have plenty of low-scoring games and closing opportunities. Jeremy Affeldt rode his plus fastball/curveball combination to the best ERA of his career, but the underlying stats weren’t as pristine. It’ll take an injury to make him a closer.

The Starting Lineup: The 26th-ranked offense in baseball can only get better in 2010, but Sabean sure loves to acquire mediocre veterans, doesn’t he? That description can pretty much describe every player in the starting lineup other than young stud Pablo “Kung Fu Panda” Sandoval, whose game actually resembles his less-popular nickname, Fat Ichiro, with its high-BABIP, high-contact, high-wire approach. It’s nerve-wracking to recommend a guy with such a high BABIP, but he seems to have mastered some ability there. Otherwise, the rest of the offense features players that are best suited as late-round positional fillers at best.

Freddy Sanchez, Aubrey Huff, Mark DeRosa, Edgar Renteria, Bengie Molina, and Aaron Rowand are all below-average fantasy players that shouldn’t be rostered in traditional mixed leagues unless they happen to be hot while your starter is injured. Only Nate Schierholtz joins Sandoval on the better side of his peak, and he has yet to turn in a Major League performance that looks anything like his Triple-A success (.925+ OPS in two seasons there). If he holds on to his job all year, he may put up a .280/20/80 season that will come cheaply and be a boon to deep league managers.

The Bench: Despite all the hand-wringing about Fred Lewis failing to develop further, the young man has done well against righties and may actually push Mark DeRosa into a super-utility role many days. He’s worth a thought or two in deeper leagues as one of the few younger players in this offense. We know who Juan Uribe is, and it’s not very exciting. Eugenio Velez is young and fast, he just doesn’t make enough contact. Travis Ishikawa is also young, and could have made a glove-and-OBP player against righties at first base, but will have to play his way through Huff to matter.

Overall team outlook: Coming off of its second straight Wild Card postseason appearance, the Rockies have found an interesting and competitive mix of youthful promise and veteran leadership. Going forward, their unique situation will continue to be the struggle to put together a workable and affordable Coors-friendly pitching staff around their strong youth up the middle.

The Starting Rotation: Coming off his second four-plus WAR season, Ubaldo Jimenez is the unquestioned ace of the staff. His ability to consistently rack up ground balls and strikeouts bodes well for his future. Some projections have him returning to the higher walk rates of his early career, but after last year’s nice walk rate, a rosier outlook on Jimenez is defensible. Aaron Cook also uses a nice ground-ball rate to forge passable real-life production, but because of his strikeout rates is usually only usable in deeper fantasy leagues.

The returning Jeff Francis has showed promise but is coming off of shoulder injuries and never really showed standout ability in either the strikeout or ground-ball categories. Jorge De La Rosa is the ultimate wild card in terms of performance. Last year, the strikeouts and walks came in bunches, and he had the best season of his career… while putting up a 1.38 WHIP. In deeper leagues, the strikeouts are worth a pick, but in normal leagues De La Rosa is only a late round flier. Jason Hammel doesn’t do enough of anything to be very interesting. If Francis is not healthy, Franklin Morales and his still-existent upside may find himself back in the rotation.

The Bullpen: Huston Street had his regular health hiccups in 2009, but he returned to dominance with a double-digit strikeout rate and a miniscule walk rate. Even conservative projections have him putting up another excellent season in 2010 and only trepidation about his health, or the slight worry that Street gets traded to a team with a closer, should cause any hesitation for potential Street owners on draft day. Rafael Betancourt and Morales lurk should one of these scenarios bear fruit, with Morales the possible long-term option if the Rockies take a step back and need to look to the future.

The Starting Lineup: You’d have to think that his scorching second half last year earned Carlos Gonzalez the leadoff role permanently, especially since early returns have him better than Dexter Fowler defensively in center field. That pushes Fowler into a platoon with Seth Smith, and since Fowler does his best against lefties, it will take a Brad Hawpe trade to recover Fowler’s (admittedly strong) fantasy upside in the short term. Hawpe will eventually go, and then this will be an outfield that will sport great D, good speed, and power alongside their ability to get on base. Buy on all of the Rockies’ outfielders outside of the defensively limited Hawpe.

Clint Barmes hit second most of last year, but that spot in the order is volatile and will probably rotate during the year. Todd Helton is the old man among the boys whose production depends on how well his back holds up, but either way he has the powerful Ian Stewart ready to knock him in. Finally, Chris Iannetta could have some BABIP-induced bounceback next year, which would get his powerful but cheap bat into fantasy lineups in leagues of all sizes in 2010.

The Bench: The loser of the Fowler/Smith battle/platoon will find himself on the bench more than he’d like. Until Hawpe leaves, though, there’s also the talented, but so far underperforming, Ryan Spilborghs languishing on the bench. If Eric Young, Jr can play a passable second base, he should be starting (and stealing bases) as soon as this year. Bringing in Miguel Olivo the same year as signing Iannetta to a long-term contract was a little surprising. Hopefully Iannetta’s play will keep Olivo and his tiny walk rate on the bench, but if Olivo starts he’s at least interesting for his power.

Overall team outlook: After 14 straight years of playoff appearances, any year without extra games is considered a failure in Atlanta. Then again, this team seems to be coming together nicely with a combination of the fruit of the club’s prodigious talent development system and some decent free-agent acquisitions. The Braves will be interesting in 2010.

The Starting Rotation: Because of their veteran status, Tim Hudson and Derek Lowe remain the titular No. 1 and No. 2 pitchers in the rotation. However, both have shown decline and Hudson is coming off of Tommy John surgery. Though both veterans could provide some nice bounce-back value in the short term, the “real” top two starters on this team are wunderkind Tommy Hanson and the surprising Jair Jurrjens. Jurrjens doesn’t quite do it with smoke and mirrors, but there’s been some luck in his numbers and he may come back to earth a little. He’s already a risk because of his lower strikeout rates.

Though the departed Javier Vazquez had a top-five season among NL starters last year, this team always seems capable of coping with loss. Even fifth starter and Japanese import Kenshin Kawakami was decent last year, and Jo-Jo Reyes and Kris Medlen are the young swingmen that have shown promise in the upper minors.

The Bullpen: Replacing two young studs like Rafael Soriano and Mike Gonzalez with old men like Billy Wagner and Takaishi Saito seems like two large steps in the wrong direction, but in terms of real-world baseball, the decisions were laudable. Instead of sinking long-term money into a fungible position, the team has two reliable veterans on short-term contracts. This could all work out and create the bullpen of a contender, or it could fall apart and the team will see a lot of Peter Moylan. Either way, the club won’t be on the hook for a ton of bullpen salary in 2010.

The Starting Lineup: Nate McLouth returns and gets a chance to improve on his poor Turner Field numbers, and he’ll be followed by a lineup that could shape up to be strong in 2010. Martin Prado gives us no real reason to doubt his natural progression and development, Chipper Jones is stellar when he’s in the lineup, and catcher Brian McCann is a young stud with real power at a premium position.

Where Troy Glaus lands depends on how his surgically repaired shoulder holds up, but as recently as 2008, Glaus was a powerful corner infielder. He could easily return to his old status. Yunel Escobar doesn’t do any one thing at a superstar level, but he has enough on-base skills to supplant a struggling Prado and enough power to fill in for an injured Glaus. He might hit anywhere in this lineup, as he did in 2009. The outfield is still up in the air, with as many as five candidates for the corner outfield positions. Melky Cabrera does just enough to guarantee at-bats, and Matt Diaz is a lefty killer at the very least. Beyond that, projecting the corner outfield in Turner Field is a mystery in 2010.

The Bench: Depending on what happens with wunderkind Jason Heyward, the outfield is in a state of flux. Cabrera and Diaz could platoon if Heyward makes the team, and that would be the best use of their talents. If one is pressed into a full-time role, that means Jordan Schafer is getting a shot to recoup his former status as a rising star. Eric Hinske backs up the corners and could be useful if Glaus isn’t healthy. Gregor Blanco can play all over the outfield, and Omar Infante will back up the infield, but neither should be relevant in most fantasy leagues.

Overall team outlook: Mantra: bad teams are where fantasy fortunes are made. There’s plenty of opportunity on this squad, with youngsters competing for three or four spots in the lineup and the Mother of All Pitching Prospects on the way. Watch the Nationals closely in 2010 because no one knows what will happen in the nation’s capital.

The Starting Rotation: You really have to be desperate to roster a Nationals’ starting pitcher in a standard mixed league next year. Even Jason Marquis was barely rosterable last year and, with his inevitable regression next year, it will get even uglier in Washington in 2010. Stephen Strasburg is only one man, and he’s not even guaranteed to show up in the capital in 2010. Instead, fantasy managers will have to sift through the wreckage that is ground-ball-inducer John Lannan, oft-injured Scott Olsen, the underwhelming-but-young Ross Detwiler, and TJ surgery survivor Matt Chico. It’s possible that someone surprises and steals a starting job from this mediocre group, because they certainly won’t have much competition – not one of the four pitchers even boasts an average strikeout rate. It’s just that, beyond Strasburg, there’s not really a prospect coming up the pipeline this year. In general, the Nats rotation is an “avoid.”

The Bullpen: After quite the makeover, the Nationals’ bully looks much improved. Gone is walk-the-lineup Mike MacDougal and in his place is the anti-MacDougal, Matt Capps. Capps might not have the velocity or the strikeout rate of an established closer, but he won’t walk an amazing six per nine either, making him a great late-round option at closer. He should be good for nice ratios and 30 saves given his BABIP and walk rate returning to normal. Brian Bruney is the gas-throwing wild man behind him, and while Sean Burnett may look like the better pitcher, some numbers just say he was luckier. Drew Storen, another ’09 first-round pick, is not far from making the Majors once he cleans up his control.

The Starting Lineup: This middling offense (ninth in the National League) boasts some underrated fantasy players. Nyjer Morgan won’t be as good as he was after the All-Star break last year, but he’s good for a decent batting average and a bunch of steals. Adam Dunn may do some damage to your batting average, but he’s almost a lock for 40 home runs and good RBI totals.

Josh Willingham and Elijah Dukes are decent fliers in deeper leagues, particularly those leagues that use OBP instead of batting average. But the real gem in this lineup is third baseman super-stud Ryan Zimmerman, who finally put together all the parts of his game last year. Some may not believe that he’s as good as he was last year, but even with a few steps back in his game, he’s a top option at a tough position. His growth has seemed organic, for what it’s worth.

Rookie Ian Desmond is expected to push veteran Cristian Guzman from shortstop to second base. In a perfect world, Guzman would never have been signed to his current contract, but that’s the Nats for you. Desmond should provide replacement-level offense at worst, while displaying average to above-average defense.

The Bench: The signing of Ivan Rodriguez is unfortunate because it pushes a young Jose Flores to the bench, but perhaps his upside will persevere. He can’t get on base, but his power is interesting. Willie Harris should be eligible at multiple positions and offers some speed to deep league benches. Justin Maxwell used to be well thought of as a speed-and-defense outfielder, but he’s getting a little long in the tooth to be considered a prospect. Mike Morse looks like the infield backup and 1B Josh Whitesell has shown that he can get on base, but we’re still waiting on the rest of his game.