Pitchers and 'Hitability'

Today, my friend and I had a conversation that I thought might interest you guys. We were talking about pitchers and their 'hitability'. Surely you've heard someone, possibly a broadcaster, talk about how a certain pitcher is very hittable, or how another pitcher is able to prevent hits. This person, unfortunately, is misinformed.

Anyway, my friend and I were talking about whether or not pitchers can do anything to prevent hits. We know that once a ball is put into play it is out of the pitcher's control, but can a pitcher throw the ball a certain way so that when it is put into play, it is hit worse than when another pitcher allows a ball to be put into play?

My friend said that good pitchers are able to limit their hits. I said that they can't. They can help determine the type of hit it is (groundball, airball, or pop-up), but cannot determine how hard it is hit or whether it is more or less likely to become a hit. To attempt - albeit crudely - to prove my point, I looked up the career Batting Average on Balls in Play (BABIP) for some of the greatest pitchers of our generation. HRs can be prevented by pitchers (by giving up more groundballs than flyballs), but hits in the field of play - I said - cannot be prevented. Here is a list of the pitchers I looked up. Keep in mind that league average BABIP is .290, so in order for my theory to be correct each pitcher should have a BABIP close to this (it can vary slightly due to luck and a tendency to give up either more groundballs or airballs, which fall for hits at slightly different rates).

Tom Glavine - .285
Johan Santana - .287
Pedro Martinez - .287
Greg Maddux - .288
Jamie Moyer - .289
John Smoltz - .290
Al Leiter - .291
Roger Clemens - .294
Mike Mussina - .295
David Wells - .300
Randy Johnson - .301

I chose these players because they are all considered good pitchers and all pitched for a good number of years. My viewpoint states that given enough time, all pitchers will put up the league average BABIP (or the variation for a pitcher with each specific GB and FB rates). Since league average is .290, it doesn't appear that any of these guys deviate too far from it. If anything, it looks like the deviation occurs in the opposite direction expected. Randy Johnson has given up more hits on balls in play than the average pitcher.

I think that this - while crude and dealing with a very small sample size - is a pretty good indicator that pitcher's can't control how many hits he gives up. It also gives further credibility to the statistics that I stress for pitchers. Since a pitcher cannot control hits or runs, we should focus only on what he can control - Strikeouts, Walks, and Batted Ball Types. The best of these Batted Ball types is the pop-up, but because this percentage is small for all pitchers I place more emphasis on talking about Groundball Percentage. Groundballs can't be hit out of the park and can be turned more easily into double plays than flyballs despite a slightly smaller Out Percentage.

I think there is a good chance that somebody out there has already proven this point - and most likely in a more scientific way - but I found the numbers above quite interesting and wanted to share them with you. Hope you enjoyed it!