One of the things that has caught the discerning eyes of Red Sox fans this season (aside from Jed Lowrie’s ability to cure leprosy) is the decrease in velocity on Clay Buchholz’ fastball. In the past, Clay’s heater sat at around 94 MPH, and was one of the faster pitches among the collective arsenal of all American League starters. This season, however, he’s been at least 2 MPH slower, and he’s certainly looked a bit more hittable than he was in his All-Star campaign.
So, I decide to take a look at all of MLB to see if there was any sort of trend, or if Clay’s situation was unique.
The following graphs lists all pitchers who had a fastball averaging at least 90 MPH in April of last season, and their change in velocity from April 2010 to April 2011. Data courtesy of Fangraphs.com. The list is sorted with the most improved (David Price) on top, and the largest regression (Ubaldo Jimenez) on the bottom.
It does appear that most pitchers are showing less velocity in 2011 than they did in early 2010. Not only Buchholz, but Jon Lester, Josh Beckett, and a slew of other starters across the league. There are some clear injury-related cases (Jimenez, Hughes), but even when you factor out those cases, the skew is clear.
I’m sure much of this can be chalked up to some sort of error term; radar guns are far from reliable and consistent. However, this will be an interesting trend to monitor over the course of the season.