Jarrod Parker's MLB Debut

Jarrod Parker might not pitch in October for the D-Backs, but he showed why he's a strong Rookie of the Year candidate in 2012 against the Dodgers on Tuesday. The ninth overall pick in the 2007 draft returned from Tommy John surgery this season to post a 112/55 K/BB ratio in 130.2 innings pitched at Double-A Mobile, and he limited L.A. to four hits in 5.2 scoreless frames in his MLB debut. As MLB.com's AJ Cassavell noted, Parker featured a diverse, deceptive mix of pitches:

Parker's fastball was consistently in the mid-90s, but he was most effective using it to set up his offspeed pitches, specifically his changeup. Dodgers hitters were constantly out in front of his changeup and slider, flailing at the pitches to produce weak contact.

Fifty of Parker's 73 pitches were fastballs, which averaged 92.7 mph and went as high as 96 on the gun. Part of the reason that L.A. hitters were out in front against Parker is that his fastball and changeup had similar horizontal movement (5-6 inches away from lefties), but the low-80s changeup dropped a half-foot more than the fastball. Parker had the same effect going on with his breaking pitches. His low-80s slider and high-70s curve both broke away from righties about six inches, but the curve broke down five more inches than the slider:

 Release velocity and movement of Parker's pitches, 9/27/2011

While I'm not suggesting that Parker will soon have a pair of Cy Youngs on his mantle, he and Tim Lincecum share some similarities that go beyond being smallish right-handers. Both have fastball/change and slider/curve combos that have similar horizontal movement, but a big difference in downward bite:

Release velocity and movement of Tim Lincecum's pitches, 2011

With Parker's fastball/changeup and slider/curve showing the same amount of horizontal break, hitters could have an awfully hard time differentiating between those pitches. Until the pitch darts down or not, that is. And by then, it's too late.