MLB DFS: Taking Advantage of Hitters With Big Right vs Left Splits

In any DFS sport, one of the best things a good player can do is pick the most underpriced players. I’ve touched on a few ways to find underpriced players using Stadiums as a factor, as well as the impact of players moving up in the lineup. There’s another set of statistics that are simple to fit into your analysis: The disparity a player has in their performance against left handed pitchers compared to their performance against right handed pitchers.

A player’s price is based mostly on his fantasy points per game, which is dependent on getting on base and hitting the ball well, factors relatively well described by OPS. But most players tend to have discrepancies in their OPS based on the whether the pitcher is a righty or a lefty. Right handed batters tend to have a higher OPS against left handed pitchers, and left handed batters tend to have a higher OPS against right handed pitchers. When the discrepancy is large, it means the player will be underpriced against their higher OPS split, and overpriced against their lower OPS split. (On a side note, a player with a large left vs right split where they perform significantly better against lefty’s will be much more undervalued than the converse, because most plate appearances a player has will be against right handed pitchers, and a players performance against right handed pitchers will  therefore dominate their price)

This data can be found on multiple websites, but I used fangraphs.com for my data on right left splits. I simply took the OPS of players over a 3 year period vs right handed pitchers, and subtracted it by their OPS vs left handed pitchers. I chose 3 years to have some reflection of improvements in a players approach against their weak side, but a big enough sample to not encounter variance induced big splits.

Here are the top 20 guys for lefties and righties.

As a reminder, strong positive values represent a player much better against rightys than leftys, and strong negative values mean the opposite.

The way to use these statistics is simple: Use a player who is good against right handed pitchers against right handed pitchers and ones who are good against left handed pitchers against left handed pitchers. This should not be your only reason to use a player, but it can make the difference when choosing between a few similar players.