Moyer is Mr. Consistency

Over the past eight seasons, few pitchers have been as consistent from season to season as Jamie Moyer. However, if you merely peruse his ERAs over those years, you probably wouldn’t come to that conclusion, as he has had ERAs ranging from a very good 3.27 in 2003 to a 5.21 mark the following season that had many assuming his career was just about over. But when we strip away some of the luck factors and look more at his peripheral statistics, we can see that the 47-year-old has been about as consistent as anyone in baseball during that time.

A good way to strip away the luck factors and still focus on a single statistic is by using Expected Fielding Independent Pitching (xFIP). Over the past eight years, Moyer’s xFIPs have ranged between 4.53 and 4.86, which clearly is a much tighter range than his ERAs. How does this compare to other pitchers, though? To answer that question, I looked at the standard deviation of xFIPs from 2003-10 for each pitcher with five or more seasons in that time frame. The following table summarizes the results:

A Mark Of Consistency
These are the top pitchers in standard deviation of xFIPs from 2003-2010. (Min. 5 seasons)

Rank	Name	     xFIP SD	Seasons
1	Cole Hamels	0.06	5
2	Mike Hampton	0.08	5
3	Jamie Moyer	0.10	8
4	Gary Majewski	0.11	5
5	Jason Johnson	0.13	5
6	Chien-Ming Wang	0.14	5
7	Kyle Davies	0.15	6
8	Chris Capuano	0.15	5
9	Brett Tomko	0.16	7
10	Victor Santos	0.19	5

Moyer has been more consistent than most of his peers when you remove defense and luck, and his steady run is longer than that of anyone who is ahead of him on the list. There were 433 pitchers who fit the above criteria, and the group had an average standard deviation of 0.72. Moyer’s peripherals have been stable enough to put him in the first percentile of consistency (on a season-to-season basis) when measured with xFIP.

How does he do it? Well, Moyer has had the right mix of strikeouts and walks to keep his xFIP stable over the eight-year sample. Looking at his pitch-type information from FanGraphs shows that the results are not completely surprising, as Moyer hasn’t really changed his repertoire during the time frame in question. He has deployed the same 81 mph fastball, 79 mph cutter, 68 mph curveball and 75 mph changeup each and every season. And since he has never relied on velocity, he hasn’t had to worry about it fading over time like most pitchers do.

Additionally, Moyer’s batted-ball profile, while not traditionally considered a peripheral stat, has looked pretty similar from year to year. Opponents have had around a 20 percent line-drive rate, and ground ball and fly ball rates right around 40 percent each. It appears that having similar stuff each year has led to similar results on balls in play, and it explains why Moyer has been able to continue to succeed into his late 40s.