John Lackey has a 46.0% groundball rate this year, more or less in line with his last few seasons, but slightly above his career average. It only makes sense that, as a guy gets older, he might evolve his repertoire to induce more groundballs, where damage can be minimized.
But Lackey hasn’t just evolved his repertoire on the year as a whole, he’s massively shifted his pitch usage within this season. Check out the four-seamer drop-off, and huge increase in sinkers (via Brooks):
And, indeed, as Lackey’s sinker usage has climbed, his groundball rate has climbed right alongside it: from 44.6% in the first half to 47.9% in the second half, including 52.4% in September and October. Lackey very much wants you to put the ball on the ground right now.
It’s no real mystery why he’s made this shift: although his four-seamer generates more whiffs than his sinker, it also leads to many more line drives and fly balls, yielding an ISO that is 61 points higher against four-seamers than sinkers. So, it’s sinker-heavy for Lackey, especially against righties. Furthermore, against righties, he’s using it most when the batter is ahead in the count. When he, himself, gets ahead, he likes to wipe batters out with his slider.
Interestingly, though, on the year, Lackey has shown an extreme penchant for starting off left-handed batters with a four-seamer, and that’s actually gone up as the year has gone on. Presumably because of the respective pitches’ movement, Lackey very rarely uses the sinker against lefties at all.
It should be no surprise, then, to learn that Lackey has a very pronounced L/R split this year: righties are posting a mere .269 wOBA, whereas lefties are way up at .326.
In the end, what’s the lesson here? Stack the lineup with lefties who are looking for a fastball early. Similarly, righties should try to keep the ball off the ground by attacking early in the count (though he’s much more balanced in his he starts off righties).