I was skimming over a Baseball Prospectus chat with Mike Fast today when I happened upon the following question and response:
Lucas Apostoleris (Massachusetts): Would you be able to elaborate on your issues with HR/FB?
Mike Fast: There are issues with classifications of fly balls for one thing, and ballparks play differently, and very few people or published stats account for either of those.
The other big issue that I have is that directionality of air balls matters a lot, and pitchers have been shown to have a repeatable skill for this. Pulled air balls go out of the park quite frequently, and opposite field air balls almost never do.
Fast's overall answer is certainly interesting, but I want to focus on the second part of his reply real quick and pull it out of a simple discussion about HR/FB. Directionality of batted balls allowed doesn't get a whole lot of talk, but it's pretty damn important. It should come as little surprise that the most damage is done on batted balls that are pulled, with the following being the 2011 AL breakdown:
Pulled: .387 average, .708 SLG
Up the middle: .284 average, .402 SLG
Opposite: .277 average, .392 SLG
It stands to reason, then, that a pitcher who allows more pulled balls will be less successful, and a pitcher who allows fewer pulled balls will be more successful, relative to the average. So without taking up any more of your time, here's a table comparing a bunch of baseball's top righties this season (note: all balls, not just fly balls):
In first, by a healthy margin, we get our own Michael Pineda. And while I don't know if he's first overall in the league - I didn't check everybody - he's at least first among this elite class of righty starters. And this is a big reason why batters haven't been able to do much damage against him on the balls they've put in play. If they can't pull the ball, they can't hit the ball with maximum bat speed.
I don't know if this is going to continue. I'd assume it'll regress at least a little bit, just because of how far away it is from the rest. But given Pineda's real velocity, perceived velocity, and breaking ball, it makes sense that batters would be off-balance and behind, so he may always allow fewer pulled balls than the average pitcher. And that would limit his home runs and extra-base hits.
Take a step back, and Michael Pineda is amazing. Take a step forward, and Michael Pineda is amazing. Michael Pineda is amazing.