The Platoon Split You May Have Never Heard Of
Writing about baseball isn’t the most predictable task. I often don’t know what my topic will be until the dust settles, hours after rummaging through a pile of numbers that, at first glance, makes little sense. For example, this article started off as an inquiry into Darin Ruf. Of all the journeymen to stop by the KBO, experience a resurgence, and return stateside, he’s by far enjoying the greatest success – who would have guessed?
As a right-handed hitter, Ruf’s primary asset is a knack for mashing lefty pitchers. He can hold his own against righty pitchers, too, posting a 126 wRC+ against them last season. But detractors might point to a .386 BABIP that buoyed much of that production. In other words, one could expect Ruf to become a bit more… rough in the future (sorry). A quick search reveals that he had a higher groundball rate against righties compared to lefties, which doesn’t bode well for future success, and not much else. The critics win this round.
Here’s the thing, though – he wasn’t alone. It turns out that in 2021, right-handed hitters had a higher groundball rate against right-handed pitchers; conversely, they had a lower groundball rate against left-handed pitchers. You can see for yourself:
| P Throws | vs. RHH | vs. LHH |
|---|---|---|
| Right | 43.4% | 41.4% |
| Left | 41.1% | 47.5% |
This is also true of left-handed hitters. Facing same-handed pitchers led to more groundballs, while opposite-handed pitchers led to, well, the opposite. The gap in groundball rate by pitcher handedness is greater for lefty hitters, though that may be influenced by the relatively few instances of lefty-versus-lefty matchups. Still, the difference, which appears on a league-wide scale, is significant enough to warrant an investigation. Read the rest of this entry »
