From SABR member Bill Petti at FanGraphs on November 16, 2012:
It’s the bottom of the eighth inning. Men are on first and third base, there’s one out and your team is down by one run. The opposing team has one of the best ground-ball pitchers on the hill, and the infield is playing back and is looking for a double play. All you need is a fly ball to tie the game and significantly swing your chances of winning.
So who do you want at the plate?
It’s likely that the opposing manager will either bring in a ground-ball specialist or just tell the pitcher to stay away from pitches that could be hit in the air to the outfield. Knowing who you’d want to hit requires an understanding of what pitches are the most likely to induce a ground ball — and what hitters manage to hit fly balls against those pitches most often.
Josh Weinstock examined the characteristics of ground-ball pitches in 2011. Generally speaking, ground balls are heavily dependent on their vertical location and vertical break. In terms of vertical location, ground-ball rates increase the lower the pitch is thrown. Pitches lower than two feet above the plate induce ground balls at a rate more than 50%. Josh also found that the more sink a pitch has, the more likely it induces a ground ball. But there was a whole bunch of overlap between sink and vertical location.
Read the full article here: http://www.fangraphs.com/blogs/index.php/when-you-really-need-a-fly-ball/
Originally published: November 16, 2012. Last Updated: November 16, 2012.