# Baseball Q: Leftie-leftie statistically valid?
**URL:** https://boards.straightdope.com/t/baseball-q-leftie-leftie-statistically-valid/70404
**Category:** Factual Questions
**Created:** [June 28, 2001, 2:04am UTC](https://boards.straightdope.com/t/baseball-q-leftie-leftie-statistically-valid/70404 "2001-06-28T02:04:03Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@The\_Raven\_1](https://boards.straightdope.com/u/The_Raven_1)
#### Post date: [June 28, 2001, 2:04am UTC](https://boards.straightdope.com/t/baseball-q-leftie-leftie-statistically-valid/70404/1 "2001-06-28T02:04:03Z")
Howyadoin,
I tried googling this one, to no avail, so here goes…
## The LaRussa Syndrome…
Is it a valid statement (within statistical error) that left handed pitchers are better at getting left handed hitters out than righties?
Thanks all,
-Rav
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### Author:  [@BobT](https://boards.straightdope.com/u/BobT)
#### Post date: [June 28, 2001, 2:12am UTC](https://boards.straightdope.com/t/baseball-q-leftie-leftie-statistically-valid/70404/2 "2001-06-28T02:12:13Z")
Do you mean taken as a whole? Every lefty batter against every lefty pitcher?
Most likely I would say that the matchup would always favor the pitcher, but I don’t have a figure.
There are always a few lefty batters who hit lefty pitchers hard. Mo Vaughn always had good success against Randy Johnson, but Vaughn is an above average hitter.
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### Author:  [@minty\_green](https://boards.straightdope.com/u/minty_green)
#### Post date: [June 28, 2001, 2:35am UTC](https://boards.straightdope.com/t/baseball-q-leftie-leftie-statistically-valid/70404/3 "2001-06-28T02:35:12Z")
I don’t have the numbers on hand, but the overall numbers I’ve seen show that leftist pitchers do slightly better against leftist hitters, and right-wing pitchers do slightly better against right-wing hitters. Not by a whole heck of a lot, but maybe .030 points or so. It’s statistically significant, at any rate.
Of course, the far smarter thing for a manager to do is to evaluate the situation, the hitter, and the pitcher. A solid righty’s lower ERA against everybody says a lot more to me than a mediocre lefty’s ERA against lefties. But as BobT points out, there are also some lefties who hit particularly well against lefies, and vice versa.
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### Author:  [@RickJay](https://boards.straightdope.com/u/RickJay)
#### Post date: [June 28, 2001, 3:59am UTC](https://boards.straightdope.com/t/baseball-q-leftie-leftie-statistically-valid/70404/4 "2001-06-28T03:59:55Z")
Almost all batters have a pronounced tendency to hit better against opposite hand pitchers, and the tendency IS more pronounced among lefties (they don’t face other lefties as often as righties face righties, you see.) Innumerable studies have been done on this and it’s basically a universal tendency, with some players having a slight disadvantage hitting against same-hand pitchers and some just completely incapable of doing it.
This, by the way, is referred to as the “platoon advantage.” When your batter is facing an opposite-hand pitcher, or when your pitcher is facing a same-hand batter, you have the platoon advantage. A righty and a lefty sharing a position and switching off depending on the pitcher are said to be “platooning.” This strategy dates back to the beginning of the century but was really popularized by Casey Stengel in the 50s.
Players who hit better against same-hand pitchers are EXTREMELY rare.
Some lefthanded batters; I’ll divvy them up by OPS (slugging percentage plsu on base percentage, a nice, easy way to gauge performance)
BARRY BONDS
vs. Righties: 1.408
vs. Lefties: 1.232
CARLOS DELGADO
vs. Righties: 1.044
vs. Lefties: .736
TINO MARTINEZ
vs. Righties: .713
vs. Lefties: .681
MARK GRACE
vs. Righties: 1.064
vs. Lefties: .718
LARRY WALKER
vs. Righties: 1.147
vs. Lefties: .953
COREY KOSKIE
vs. Righties: .790
vs. Lefties: .562
JIM THOME
vs. Righties: 1.047
vs. Lefties: .798
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### Author:  [@Dignan](https://boards.straightdope.com/u/Dignan)
#### Post date: [June 28, 2001, 5:45am UTC](https://boards.straightdope.com/t/baseball-q-leftie-leftie-statistically-valid/70404/5 "2001-06-28T05:45:49Z")
I’ve always wondered why it is that opposite handed (from the pitcher) hitters have the advantage. Is it simply because a righty’s curve or slider will break away from me (a righty) giving the pitcher the advantage? I would think that outside pitches are easier to hit than inside (because of extension). Then again, I never played past elementary school.
I remember in little league that a pitcher of ours (a lefty) couldn’t pitch to lefties. No problem with righties, but in the rare case he’d face a fellow southpaw, he was wild.