At the end of May, Carlos Correa possessed a .253/.348/.414 line that didn’t much resemble the numbers from his Rookie of the Year debut. The walks were there, the strikeout rate was about the same, but the defense was down and the power was out. Hey look at him now! He’s got a .268/.366/.477 and is approaching last year’s weighted-offense mark. Let’s look at what happened in June.

The easy answer is that Correa has been hitting the ball harder. He’s hitting for more power, duh. But if you split the season into two halves, each featuring roughly significant samples of balls in play — 100 balls in play is a good number, and most everyday players are at around 200 right now — you’ll see that Correa has improved more than almost everyone in baseball.

We talk about launch angle being as important as exit velocity, so let’s limit the angles to the ideal angles for line drives and power, 10 to 30 degrees. Here are the biggest gainers with more than 100 balls in both samples and more than 20 in the ideal angle band.

Okay, so he’s hitting the ball harder. Real hard. That velocity from the latter sample of batted balls is second in baseball in the ideal launch range, and second to Billy Butler (!) who’s recorded only 17 balls in that grouping.

Let’s try and see if it was more of a mechanical thing — which we might find in an angle change — or more of a selectivity thing.

If we look at his traditional batted-ball-mix markers, it looks like — paradoxically — Correa was hitting for less power when he was hitting too many fly balls. He got back to a more level swing in the second half of the first half, one that more resembled the mix he had late last year.

But the line drives in there mess the whole thing up, since they are sodden with bias. Let’s look instead at angle. Last year, Correa recorded 30.5% of his balls in play in that ideal band. Until May 15, Correa had recorded 24.7% of his batted balls in it. Since then, it’s up to 31.6%. So, to some extent, Correa has leveled out his swing and rediscovered what he had last year.

He’s also changed the pitches at which he’s swinging, which makes sense. You have different angles to different pitches. Look at what he was swinging at earlier (left) and where he’s been swinging since (right), and you can see that he’s laying off the low pitch more often now. That means fewer fly balls, but it also obviously means better outcomes for his particular swing.

This should have some implications for his pull percentage, too, you’d think. He’s swinging at a lot of stuff inside, and has been working on the inside pitch his whole career. And it does!

Once again, Correa has gotten back to pulling the ball more. But you now see why he’s hitting for more power with fewer fly balls. He was going oppo on those fly balls before, which leads to more cans of corn. Now he’s pulling his balls with more authority, and swinging more like he did when he was at his best last year.

Yes, Carlos Correa is hitting the ball harder. But it’s because he’s become more selective in the zone, and he’s pulling the right balls more often. It’s simple, and yet it’s complicated.