The graph above charts the number of pitches Roy Halladay has thrown at each velocity along the spectrum in which his cutter and sinker sit, from 2009-2011. On top of that, colored lines indicate his average velocity for the two pitches for the entirety of 2012 (yellow), his pre-DL stint (red), and his post-DL stint (blue).
This is another way of visualizing what we already know, but I thought it was worth looking at. While Halladay’s results have been undeniably better since his return (in particular, his strikeout to walk ratio has jumped back up to a Doc-ian 7.5), the underlying issue hasn’t necessarily been fixed. By itself, the fact that his velocity is lower after the DL stint shouldn’t be sounding any alarms. Splitting up the sample like this in the first place is nudging us toward Mike Fast no-no territory. More importantly, though, it’s only natural to expect flagging velocity when you drop a 6 week rehab period into the middle of a 35 year-old veteran starter’s season. Still, it would be comforting to the more worry-prone of us to see some immediate improvement, if only for the assurance that next season will be another 200 or so innings of the usual Doc.
There is also the possibility that the nagging lat injury is hampering Roy’s command. In comparison to previous seasons, Halladay has had problems getting his cutter down and in against left-handed batters, and his sinker down and in against right-handed batters (click for larger):
In the case of the cutter, lefties in 2012 are chasing less (21.1% in 2012 to 33.3% in 2011, putting it in play more (47.9% to 44.2%), and managing a .336 wOBA as compared to .209 in 2011. For the sinker, righties in 2012 are swinging more (49% to 43.1%), missing less (6.8% to 13.9%), and posting a .309 wOBA as compared to .219 in 2011. In all of these cases we’re talking about a sample of around 500 pitches, and we can’t say for sure that it’s linked to his back issues, but it’s not a comforting picture. Given where the Phillies are in the standings, having just decided against pushing Vance Worley any further, it’s still worth considering the merits of giving Halladay the extra rest, in the effort to dial his velocity back up to previous levels by opening day of 2013.