Foul Ground Home Field Advantage

By no means am I a veteran of the press box. But already I’ve tapped into a strange phenomenon that may be universal to all baseball writers — I’m not rooting for a team, I’m rooting for my story.

For example. Going into the American League Division Series, I decided I would do some research on the home field advantage offered by the extensive foul ground in Oakland. After gathering some quotes — easy, considering the optics of Josh Donaldson, running forever for a foul ball — I was ready for a Game-Changing Moment. A foul ball over the bullpen mound in the late innings. A missed foul ball by the Tigers. I was rooting for a foul ball.

I didn’t get my big foul ball, or you’d have gotten this story, with a much different lede, weeks ago instead of now. Looking back through my numbers, though, there was a surprise. More the kind of surprise you get when you turn on the television in the fall and get a random Arizona Fall League game. More that than the sort of surprise that Nate McLouth got when Donaldson did this:

The stage was set for this sort of surprise during the ALDS. Bob Melvin said he chose Daric Barton for a few of those games because the first baseman “covers a lot of ground” and would help specifically because of the foul ground in Oakland. “You have a hundred-something feet out there,” Barton said. Barton added “there’s a lot of outs out there,” but admitted that “they say it’s worth about ten-to-fifteen points on your batting average.” He laughed about that one, though — that cuts both ways and “it’s so frustrating.” But Barton felt that he knew the ground well and that there were plenty of times when he got to balls that people felt were automatically in the seats.

Watch that highlight of Donaldson, and listen to Barton talk about how he can avoid the mound, and about plays like the one where Trevor Crowe went after a foul ball and fell on the bullpen mound, and it’s easy to think: Oakland must get home field advantage from their intimate knowledge of the foul ground.

Turns out, not so much. Check out the home and away foul ball outs by stadium, 2012-2013:

TFO = total foul outs in the stadium
RTFO = foul outs that occurred while the road team is batting
HTFO = foul outs that occurred while the home team was batting
HFA = RTFO – HTFO

Yeah, so Oakland, over the last two years, has played almost exactly neutral in foul grounds, despite having the largest foul ground in baseball.

Thanks to Bill Petti’s Interactive Spray Chart Tool, we can see, graphically, how different the foul grounds are compared to, say, the number one team in foul ground home field advantage: the Philadelphia Phillies.

You can’t quite blame this on personnel. According to Josh Reddick, the outfield portion of the foul ground is about the same as most parks, and he figures that it’s mostly on the first baseman and third baseman to get to these balls. The combined UZR over the last two years for the first and third baseman on the Phillies (-10) and Athletics (+31.3) has the signs reversed if you want to blame this phenomenon on the defenders on the corners. Shortstops and second basemen can get to some of those balls, too, though — the range components for the infield in Oakland (+22.4) and Philly (+24.9) tell a bit of a different story.

So let’s put the foul ground home field advantage up against the UZR infield range factors for the past two years. It doesn’t seem to match up.

So if it’s not about the field itself, and it’s not about the interaction between the field and the specific players about it, is there another source of foul-ground-inspired home field advantage? What about day/night splits? Perhaps some players know their foul ground better and can navigate it better at night?

Well, it works in Philadelphia for some reason. Guess I’ve got a story for the next time Cody Asche ranges deep into foul territory in a big spot in a big night game for the Phillies next year.