Austin Jackson’s ground ball spike

The return of Austin Jackson as a viable, impactful offensive presence has been one of the great happy surprises for the Indians this year. By several measures the man who was expected to fight for playing time with a host of other outfielders has been one of the best hitters on the team by several different rate stats, and a murderer in particular of left-handed pitching. He also flashed intriguing power in the first half. I even wrote about adjustments he'd seemed to have made to get the ball in the air more, since he's 30 years old and can't rely on his legs. Since the All-Star Break (and a couple short stints on the DL) he's been a bit less poppy, and some of his batted ball profiles have shifted. Hopefully it's not a backslide.

Here's what I mean about the batted ball profile:

Before the break, Jackson was fly balls and liners, eschewing the higher BABIP grounder in favor of doubles and a few home runs. to be clear, this hasn't really caused a lot of suffering in his actual offensive output:

His batting average is higher, but he on-base and the slugging are down a bit even with more hits falling. And that’s with his BABIP has shooting to .400. He's always had a high BABIP due to the ground balls and the speed, but that was theoretically a Jackson of a bygone era. It seems like he's been kind of lucky, but the power has slipped, and he's reverted to the Jackson of old. What's to blame?

It’s weird because he’s being treated very similarly, as far as pitch type:

Perhaps a smidge more breakers and off-speed pitches than before, but that can’t be the culprit, can it? Jackson is a fastball hitter, particularly sinkers. He's hitting .422 on them this year with a .654 slugging percentage, while on four-seamers it's a .292 batting average with a .494 slugging percentage. On changeups, he's hitting a meager .167 while slugging .306. One would think he would have gotten a steadier diet of these pitches, but nothing remarkable. The only troubling part is how he’s swinging and missing at these off-speed and breakers in August and September:

That massive dip in July is his time on the disabled list. Hard to whiff on pitches when you don’t play. He’s still hitting fastballs as consistently, but could these whiffs also be involved in some kind of soft contact? His walk rate is down to 8.5 percent from 13 percent in the first half, while the strikeout rate has leapt four points to 22.5 percent. As mentioned before, he’s a big time fastball hitter. Maybe he’s taken to chasing after them too much, and that added to whatever sapping injuries he still has hanging around from that month on the shelf could be causing this grounder problem. It’s weird because despite his love of the heater, they’re actually throwing them higher in the zone at him:

Without knowing if he’s feeling some kind of strange pain, or just wants only baseballs down in the zone, I’m not sure why he’s suddenly hitting more grounders. It stands to reason the higher the ball, the more they’d be in the air. But he’s refuting that idea.

Jackson is going to be a key piece in the Indians lineup and defense in the postseason. He is the best defensive outfielder they have now that Bradley Zimmer is out, and his bat has spoken volumes so far. If regression does hit because those grounders start finding gloves and he can’t get the launch angles he was getting in the first half, it’s going to be “defensive specialist” Jackson instead of the “5 Tool Superstar” Jackson that has been such a revelation this season. The sample sizes on both sides being relatively small, it’s wrong to worry. But as with Jackson’s elevated batted balls and resultant power surge early in the season, it’s definitely something to watch.

Also why more “Action Jackson” puns haven’t been made at his expense this year baffles me. I am partially to blame.