Back in August, I wondered if the homer-happy tendencies of the new Yankee Stadium had an effect on how the Yankee hitters put balls in play. The theory was simple: even if stadiums do not actually play to their commonplace perception (i.e. maybe Yankee Stadium was actually a pitcher’s park), players will respond based on what they think is true. Looking at the results, Tom Tango commented:
That’s an average of around +4% more FB per BIP at a team level, which must be enormous.
I would guess, total guess, that 99% of all players with at least say 400 BIP would be +/-5% year-to-year. I’ll further guess that all teams would be +/-2%. So, when I see a team level change of 4%, that definitely seems to imply something.
If it’s a question of players responding to the perceived expectation of the park, it would be interesting to see if this change happened at a particular moment. Remember, FB/BIP is a very telling stat that quickly shows real changes in talent.
Based on that response, I decided to look at another park thought of as being particularly hitter-friendly: Citizens Bank. CBP opened up in 2004 and quickly got the reputation of being a nightmare for pitchers and a haven for hitters. But did the players actually respond to that possible incentive? I looked at all of the Phillies hitters with at least one-hundred plate appearances from 2004, with the only exception being Ricky Ledee, who split time with the Giants, making his results tainted. Here’s what I found:
Player 2003 FB% 2004 FB% Difference Jimmy Rollins 34.4 35.8 1.4 Bobby Abreu 26.7 36.8 10.1 David Bell 37.4 36.6 -0.8 Jim Thome 38.8 45 6.2 Placido Polan 28.6 29.1 0.5 Mike Lieberth 36.7 45.5 8.8 Pat Burrell 43.8 45.4 1.6 Marlon Byrd 25.4 27.5 2.1 Jason Michael 34.5 39.5 5 Chase Utley 36.3 34.4 -1.9 Tomas Perez 32.6 48.4 15.8 Doug Glanvill 36.9 37.4 0.5 Todd Pratt 33.7 34.1 0.4
Yowzers. Add up all those percentages on the far right and you get a net increase of 49.7. Of the thirteen players with the most plate appearances for the 2004 Phillies, eleven of them increased their amount of fly balls per ball in play, with the only two exceptions being Bell and Utley.
But if we look at the guys who would want to get the most out of their fly balls, then we should see how the sluggers changed their game. In 2004, Thome hit forty-two homers, Abreu hit thirty, and Burrell hit twenty-four. Each saw an increase in their fly ball rates, capped off by Abreu’s dramatic 10.1 increase from the year before. It also would’ve seemed impossible for Burrell to hit any more fly balls than he had the past year, but he was able to muster a modest 1.8 increase. Mike Lieberthal also went from a pedestrian 36.7 FB% in 2003 to being in the top twenty-five highest in baseball in 2004.
We can’t exactly get into the minds of the Phillies hitters, but I think this comes pretty darn close, and that says a lot.