Don Mattingly’s First Mistake

Don Mattingly won his first game as a major league manager Thursday night, as his Los Angeles Dodgers knocked off the San Francisco Giants behind a stellar pitching performance from Clayton Kershaw. However, while all of his moves “worked” in retrospect, Mattingly made one big rookie mistake that could have cost the Dodgers the game — he left Kershaw in the game too long.

In the bottom of the sixth inning, the Dodgers capitalized on some defensive miscues to break the scoreless tie and take a 1-0 lead. However, after Rod Barajas lined out for the second out of the inning, Bruce Bochy opted to intentionally walk Jamey Carroll to load the bases and bring Kershaw to the plate, forcing Mattingly to choose whether to let Kershaw hit in order to pitch the seventh inning or go to the bench and then use a reliever to get the next three outs.

Mattingly chose to stick with Kershaw, which is understandable considering how well he had been pitching. However, like football coaches who punt far too often on fourth down, that’s a conservative call that actually lowers a team’s chances of winning.

Let’s start with Kershaw’s offense — he’s one of the worst hitting pitchers in baseball, having accumulated just 10 hits (all singles) in 132 major league at-bats. He’s drawn just four walks and struck out 46 times, and his lack of ability to hit the ball with any authority has led to a miserable .076/.103/.076 career mark. And remember, that’s his line against pitchers of varying quality — if he consistently had to face Tim Lincecum, his numbers would be even worse.

Charitably, we can say that there was approximately a 7.5 percent chance that Kershaw would have reached base safely in that situation, extending the rally and pushing the Dodgers’ lead to two or three runs. Those odds are not good, and predictably, Kershaw bounced out to first base to end the inning.

If Mattingly had chosen to pinch hit, he likely would have turned to Marcus Thames or Xavier Paul. While Paul would have given them a left-handed bat to counter the right-handed Lincecum on the mound, he’s also a young player without much of a track record in the major leagues, so the safe assumption is that Thames would have been the one to get the call.

While he’s on the roster for his ability to hit lefties, Thames still holds a career line of .236/.296/.480 against right-handed pitchers. Again, we have to adjust those numbers downward to adjust for Lincecum’s abilities and the fact pinch-hitters fare worse than normal on average, but Thames still had at least a 20 percent chance of getting hit and another 7.5 percent chance of getting on via hit batsman, walk or error. Thames was four times as likely to produce a positive outcome in a critical situation in which any base hit would have likely plated multiple runs, and he also presented a real opportunity for a grand slam that would have essentially put the game out of reach.

There was a significant opportunity cost to letting Kershaw bat in that situation, and Mattingly traded away a real chance for an expanded lead for the right to keep Kershaw on the hill in the seventh inning. Kershaw rewarded his manager with a three-up, three-down inning, but given that he was facing the 6-7-8 hitters in the Giants’ order, this was a job that could have easily been entrusted to Matt Guerrier.

After all, the Dodgers thought enough of Guerrier to sign him to a three-year contract as a free agent this winter. Guerrier is not nearly as good as Kershaw, but he’s an effective reliever, and he could be trusted to get out Miguel Tejada, Brandon Belt and Pablo Sandoval, especially with the pitcher’s spot looming if the Giants were able to get a rally going. However, this isn’t about Guerrier — the run expectation of the two situations is so large that Mattingly could have handed the ball to almost any other reliever in the seventh inning and still come out ahead.

The difference between Thames and Kershaw hitting in that situation was more than two-tenths of a run in expected value. Kershaw’s career 3.17 ERA translates to an expectation of .35 runs allowed per inning, so Mattingly could have chosen a pitcher with an ERA of 5.00 (.55 runs per inning, creating that same two-tenths of a run gap) and had it be a push. Using Thames to pinch hit and any reliever with an expected ERA below 5.00 would have been a better bet than letting Kershaw bat for himself and then pitch in the seventh inning.

In the end, it didn’t end up costing the Dodgers a win, but this is the baseball version of punting on fourth-and-1 from your opponent’s 30-yard line. Mattingly can create a significant advantage for his team by more aggressively pinch hitting for his starting pitcher in high-leverage situations and accepting the fact that, while the reliever will not be as good as the pitcher you’re replacing, the drastic upgrade at the plate with a chance to blow the game open is more than worth it.