Is baseball biased toward left-handed pitchers? Indeed it is, says David A. Peters, Ph.D., McDonnell Douglas Professor of Engineering at Washington University in St. Louis (and uber baseball fan) and he says he has the data to prove it.
There's no question left-handed pitchers, even less than great ones, can last a long time in baseball. But 90 percent of the world is right-handed yet only 75 percent of baseball players are. Is that because left-handed pitchers do better against right-handed hitters so teams develop more left-handed hitters toi counter that or is it part of a vast, left-hand conspiracy?
To begin with, it's not just pitching, Peters says, left-handed hitters have an advantage in their own right. "A right-handed batter facing a right-handed pitcher actually has to pick up the ball visually as it comes from behind his (the batter's) left shoulder. The left-handed batter facing the right-handed pitcher has the ball coming to him, so he has a much clearer view of pitches."
Then, Peters says, consider the batter's box. After a right-hander connects with a ball, his momentum spins him toward the third-base side and he must regroup to take even his first step toward first base. In contrast, the left-hander's momentum carries him directly toward first.
"The left-handed batter has a five-foot advantage over the right-handed batter," says Peters. "And that means the lefty travels the 90 feet to first roughly one-sixth of a second faster than the righty. That translates to more base hits for the left-hander, whether singles or extra base hits because lefties are getting to the bases more quickly."
The left-handed pitcher is also more difficult to steal second base against since, from his stretch, he peers directly at the runner; the right-handed pitcher must look over his shoulder and wheel to first base, giving the runner more of a warning of the pitcher's intent.
The whole game sounds like a conspiracy against right-handed people in that light but the advantage doesn't apply everywhere. Positions advantageous to southpaws are pitching, first base and right field. For those positions the advantage is the favorable angles lefties get, enabling them to throw the ball more quickly across the diamond to second, third and home.
The least likely position for a left-handed player? Catcher. It is difficult for a southpaw catcher to throw over so many right-hand batters.
"It wasn't all that long ago when first basemen were predominantly left-handed and most right fielders were left-handed," Peters says. "That has changed at least since the late sixties."
It doesn't end there. There's even a bias toward the lefthander in ballpark design. Right field in most parks (just think of Yankee Stadium and Fenway Park) is usually shorter than left field because of the preponderance of right-handed hitters.
While traditional thinking holds that the right-handed batter has the advantage over the left-handed pitcher, because the breaking ball goes into the batter's power threshold, it's not always the case, says Peters. And it's that familiarity thing again.
"Because only 10 percent of the population is left-handed, kids grow up and mature in baseball seeing a left-hander just 10 percent of the time they bat," he says. "So, it can be hard for both lefties and righties to face a southpaw. It's why some left-handed batters look dreadful matched against a lefty."
Some batters don't like facing southpaws because their ball is purported to have a natural movement away from a right-hander and into a lefty.
"There's no scientific evidence to support this, but I wonder if lefties get that movement from learning to write in a right-hander's world," Peters says.