Forcing a Reason to Worry About Mike Trout, Again

I wrote something like this before, in the beginning of May of this season. During an arbitrary stretch between April 19 and May 14, Mike Trout struck out in 31% of his plate appearances, posting a .722 OPS. I identified the strikeouts as something to pay attention to, and then from May 15 through the All-Star break, Trout struck out in 20% of his plate appearances, posting a 1.111 OPS. So. Obviously, Trout adjusted to whatever needed to be adjusted to, or alternatively, the randomness swung in the other direction. For a while, it was easy to forget that Trout had ever slumped.

But now we’re back! Having learned nothing from the first go-round, I’m here to tell you to worry just a little bit about Mike Trout’s strikeouts. Since the All-Star break, Trout’s whiffed nearly 30% of the time, and he’s managed an OPS under .800. He’s still been a good player. He’s still been a terrifying player. He’s still, as of this moment, the almost certain winner of the American League’s Most Valuable Player award. But we’re obligated by social contract to write about Trout at any opportunity, and there are signs pitchers are finally trying to take advantage of his vulnerabilities. You know the ones. You’ve thought about them for hours.

Let’s summarize by splitting Trout’s season at the break. Here is what’s happened with a few numbers:

• K% – BB%: worse by 9.5 percentage points in the second half
• Fly ball%: up six percentage points
• Pop up%: up seven percentage points
• Fastball run value: down 1.6 runs per 100 fastballs
• Contact%: down three percentage points
• Zone%: up four percentage points
• wRC+: down 59 points

Everything kind of leads to the last bit. Trout’s made less contact, and he’s put more balls in the air, generally more weakly. So while he’s still been a good hitter the last couple months, he hasn’t been the terror he previously was. Now pay extra attention to that part about fastball run value. Trout, against non-fastballs, has mostly been fine in the second half. But fastballs have given him fits. And now we get to talk about that vulnerability we’ve pointed out here before.

Trout might be the game’s premier low-ball hitter. My theory is that’s why he’s had so much success against Felix Hernandez. Felix has tried to pitch to Trout right around where Trout likes to be pitched. This year Trout has slugged .664 against pitches no more than 2.5 feet off the ground, and .682 against pitches no more than 2 feet off the ground. Meanwhile, he’s slugged .353 against pitches at least 2.5 feet off the ground, and .104 against pitches at least 3 feet off the ground. Trout, probably, isn’t as extreme as those splits suggest, but he’s got the swing to destroy pitches around the knees, and that can leave him open against stuff by the belt.

So how has Trout been pitched in the second half? Some numbers, from Brooks Baseball:

First half: 39% four-seamers
Second half: 49%

First half: 23% sinkers
Second half: 16%

Trout has one of baseball’s biggest increases in four-seamer rate, and those are pitches you tend to find more up in the zone. He’s had a similar but smaller drop in sinker rate, and sinkers, of course, hang around the bottom of the zone when thrown properly. Those numbers hint at something; these numbers demonstrate something. From Baseball Savant:

First half: 42.5% pitches at least 2.5 feet off the ground
Second half: 49.0%

It’s not the very biggest increase in baseball, but it’s among them. Pitchers have been more willing to challenge Trout up, and in the meantime he hasn’t quite been himself. Or he’s been exactly himself, only against a different array of pitches than he’s used to. In the first half, he saw 38% four-seamers with two strikes. In the second half, he’s seen 50%. Those pitches are more often up, and they’re also a little more often away, just to try to keep Trout from pulling the ball like he likes.

This isn’t an easy thing to see pitch-to-pitch, especially since there’s a difference between pitch idea and pitch execution. Just because a pitch went up or down doesn’t mean that’s what was supposed to happen. But just as a maybe-example, here’s an at-bat between Trout and Colby Lewis from the first half of the season:

Everything down, but for a mistake slider middle-middle. Here’s Trout against Lewis in the second half, in the same ballpark with the same catcher:

Fastballs up. Four of ’em. Colby Lewis doesn’t have a spectacular fastball, but everything looks faster high and tight, and Trout couldn’t catch up. This is one example that might not even be one good example, but the numbers speak for themselves. Trout’s been pitched more often in just the way it seemed like would be a good idea a few months ago.

I’ll note, also, that Trout hasn’t just struggled with four-seamers — he’s also had issues with those sinkers. But, the usage of one pitch can have an effect on the success of other pitches, as everything’s related. Pitchers are more often changing Trout’s eye level. There’s also this, from Brooks Baseball: in the second half, pitchers have thrown 26% fewer sinkers in the zone, and 33% more sinkers in just off the plate. So you’ve got Trout seeing more four-seamers up, and more running fastballs in on the hands. Then the breaking balls get separated from the fastballs, as pitchers open up almost every quadrant.

I have one odd question that might seem unusual: how much of this is because of Trout, and how much of this is because of the pitchers the Angels have faced? The Angels, as a team, have seen baseball’s second-highest increase in four-seamer rate since the break, and they’ve seen baseball’s greatest decrease in sinker rate. Trout can’t explain all of that. Maybe this is less about preparing for Trout, and more about a run of arms more likely to throw high fastballs. That seems like silliness — it seems like Trout would demand particular attention — but then, pitchers hadn’t really adjusted to Trout before, so maybe this is a fluke. It perhaps shouldn’t be a fluke, but we’ll see how it continues.

And we’ll see how Trout performs. We know he’s been far better on low pitches than high pitches, but maybe he’s been specifically targeting low pitches. If he is deliberately getting pitched up more often, maybe Trout starts to look for that, and maybe Trout starts to punish that. Maybe that then leaves him a little more vulnerable to pitches at the bottom. Maybe Trout’s actually able to cover all areas. Or maybe it’ll just turn out that the best player in baseball can be exposed around the belt and the belly button. If so, it feels like it shouldn’t have taken this long, but when you’re told over and over to try to keep the ball down, it turns into a personal strength, and, who would pitch away from their strengths? I mean, how good could a hitter possibly be?