When you’re watching baseball on TV, you’ll sometimes hear the analysts comment that a manager is bringing in a particular pitcher to face a particular batter because one of them hits or throws from a particular side…
Is this determination just made on an ad hoc basis depending on an individual batter’s strengths against right or left handed pitchers, or is there a pattern to which handedness is more effective against which?
There are many individual differences. Sometimes they’ll put up a statistic that Hitter A hits better against lefties, for example. Generally speaking, I believe that a righty bats better against another righty and vice versa.
I should also have asked part B of the question, which is:
Why would it make that much of a difference?
Traditional wisdom is that a right-handed batter will hit better against a lefty because he can see the ball for a slightly longer period of time. When you are right-handed, a righty pitcher - assuming he throws overhand - seems to kind of bring the ball from behind your head; you can’t see it at first. That doesn’t happen with a lefty pitcher. Vice versa with lefties and righty pitchers. Thus, managers try to bat righties against left-handed relievers and the other way 'round.
It’s not always actually true, but they stick to it dogmatically at times.
oops. I said it backward. :smack:
The key matchup is lefties vs. lefties. For whatever reason, probably because there are so much fewer left-handed pitching, lefty pitchers seem to have more of an advantage over lefty batters than righties vs. righties or any other matchup. Like what Marley23 said about the visibility issues, it’s mostly a matter of the hitter’s perspective. A curveball or slider or any other breaking pitch from a lefty will look like it’s aimed straight for a lefty batter’s head, and then break out over the plate. A righty throwing the same pitch will appear to be throwing the ball so it breaks right towards the bat of the left handed hitter. When you see a curveball buckle the knees of a hitter, that’s what caused it.
That’s also why you’ll see lefty relievers who sometimes come in to face one left handed batter and then come out of the game. Since righties are more used to batting against righties, you wouldn’t normally see a right handed reliever “specialize” in getting out right handed batters.
I think your explanation is correct, and it’s true across sports. Lefty tennis players often say that other lefties give them the most trouble because they are accustomed to playing righties, and returning serve can get much harder as the ball will rotate in the opposite direction. Similar troubles plague left-handed boxers.
God, I sound like I can’t speak English. -There IS so much fewer-
Anyway, even in basketball or football, people with left-handed releases can catch defenses off guard. People are just less prepared against left handers because they usually haven’t seen much of it before. Heck, a bunch of weak hitting middle infielders over the years have become switch hitters just so they wouldn’t have to see a breaking ball coming at them.
I believe the difference is in how the ball curves toward or away from the batter. A right handed pitcher’s curve will break toward a left handed batter and away from a right handed one. It is easier to track a ball curving toward you than away from you and thus easier to hit.
The difference is real and significant. The same batter could easily be a .250 against a pitcher of the same handedness and .300 against opposite handed pitchers. Don’t exaggerate this difference, it is only one extra hit in every 20 ABs, but any baseball will understand the difference. As for explanation, it is very likely the difference between a ball curving away and one curving towards you, but I know of no actual tests of this hypothesis (nor do I see how to test it). Presumably a screwball pitcher (whose pitches curve the opposite way) would have stats more like those of an opposite handed pitcher, but I don’t know if that is the case. But the statistical basis of this difference is undoubted.
The difference is virtually universal. It is not just accepted wisdom; it is true of 99% of all major league hitters that they will hit better against the opposite hand. Very, very, very few batters have “reverse platoon splits.” Of the 400-500 position players in the major leagues at any one time, it would be quite remarkable for more than a dozen to have long-term reversed platoon numbers. There are many players who are excellent hitters against one type of pitcher and utterly useless against the other.
The reason is twofold:
As Hari Seldon suggests, the exception to this is screwball pitchers, like Fernando Valenzuela. Hari, yes, it’s true; dedicated screwballers have platoon splits like opposite-handed pitchers. The screwball breaks the opposite way - the only pitch than does this - and pitchers like that tend to reverse the advantage. I once saw Roberto Alomar, a switch hitter, deliberately hit from the wrong side of the plate to account for this; he batted lefthanded against the lefthanded Jim Abbott, and sure enough, he hit a home run. But there are very few screwball pitchers.
Familiarity is not what causes this effect, since righthanded batters have a platoon disadvantage against righthanded pitchers. Lefthanded batters do tend to have a WORSE platoon split because of familiarity, though.