In the fantasy baseball lexicon, “platoon” is a dirty word. Few fantasy team owners want to hear that one of their players is being benched against either left-handed or right-handed pitching.

But in leagues that allow daily lineup adjustments and enough roster room to accommodate extra batters, platoons represent a tremendous buying opportunity.

Take Seth Smith.

Smith is a smooth-hitting left-handed batter in a crowded Colorado Rockies outfield. Because he competes for playing time with Carlos Gonzalez, Brad Hawpe, Dexter Fowler, and Ryan Spilborghs, Smith doesn’t play every day. That doesn’t make his playing time unpredictable, though. Throughout this season, Smith has consistently gotten starts against right-handed pitching. 

On those days, he’s been fantastic. In 56 games he’s started this season, Smith has posted an .840 OPS. To put that in context, it’s top 50 in the MLB this season, ahead of Alex Rios, Carlos Quentin, and Justin Upton, to name a few players who dwarf Smith in ownership percentage.

The fact that Smith has been so valuable in games he’s started shouldn’t come as much of a surprise. Over the years, Smith has feasted on right-handed pitching. Since 2008, Smith has an OPS of .911 against right-handed pitching. Only 28 batters with at least 400 AB in that time frame can claim a better record versus right-handed pitchers. He’s bested players like Ryan Braun, Chase Utley, and Evan Longoria in that category.

The reason that Smith doesn’t play every day? Well, a crowded Colorado Rockies outfield is one factor. Another is that Smith doesn’t fare as well against left-handed pitching. His career OPS versus lefties is .622, albeit in a relatively small sample size.

Still, given the opportunity to play Smith on days he’s starting, what fantasy owner couldn’t have used these stats to date: a .281 AVG, 11 HR, 31 RBI, and 36 Runs.

The stats are even more impressive when paired with a player who might have been activated in place of Smith when the Rockies outfielder had the day off. 

Let’s assume a team owner has gotten 56 games from Smith and another 45 games from a replacement-caliber player. What kind of stats would be required from Smith’s fantasy platoon partner to match Jayson Werth’s 2010 production of a .292 AVG, 15 HR, 64 Runs, and 56 RBIs? Answer: Not much. 

Werth is owned in nearly every league, whereas Smith is owned in less than 10% of leagues. Pairing Smith with another discounted player like J.D. Drew or Jason Kubel offers aggregated production that can potentially surpass the offerings of a player like Werth.

Consider this a market inefficiency if you’re in a league with daily transactions. For years, real-life MLB managers have been exploiting platoons. For owners in roster-flexible leagues willing to do some daily research on match-ups, having a fantasy platoon can be just as rewarding.