Austin Slater had an opportunity to secure the starting left fielder job last season, but his bat never took off in the big leagues. In 225 plate appearances, Slater hit just .251/.333/.307. It was certainly a disappointing outcome, especially since Slater was smoking the ball for the first two months of his season. The problem that he was smoking the ball on the ground where the best he could hope for was a single.

Among batters with at least 200 plate appearances, Slater had the highest groundball rate in the majors last year at 63.1 percent. Only one qualified starting pitcher has a groundball rate above 60 percent, so it was as if Slater was facing an elite groundball pitcher in every at-bat.

When Slater sat down with our own Doug Bruzzone, he relayed that he spent the offseason retooling his swing at the behest of the front office. While one of the goals was to get Slater off the ground, most of the work centered around correcting his bat path. In his words:

The launch angle and loft, they’re the big buzzwords now. But hitters have been doing that forever. I think cleaning up of bat path is another way to put it… Hitters have always done it, but creating the launch angle and loft is a direct effect of cleaning up your bat path and how you enter the zone.

Austin said that in correcting his bat path, he needed to stay within the strike zone longer and stay behind the ball. Previously, Slater was swinging down on the ball and when a down-swing meets a ball that’s moving downward, the ball is going on the ground. Now, Slater is lining up his bat path with the trajectory of the pitch.

The new swing has helped Slater immensely. Before his call-up on Monday, Slater put up a .308/.436/.529 slash line with 12 homers. Most encouragingly, his groundball rate of 46.7 was the lowest of any professional season, no matter how brief the stint. The success carried over to his 2019 debut when he went 2-for-5 with a home run and a triple.

This season, he’s had to wait while a revolving door of other left fielders got a chance ahead of him, but now he’s back in the majors and hoping to stick. Last night was the first time we got to see Slater’s new swing, and more importantly, this is the first time we’ve gotten to see his new swing with major league camera angles.

Here’s what Slater’s swing looked like before. On this pitch, Slater hit a low-liner into the right-center gap for a double. His coaches at Stanford would have been proud.

Here’s a side view of Slater’s homer last night.

I’m mostly unequipped in analyzing a hitter’s swing, so I’m not coming at this from the mindset of a hitting coach, but more from a kid doing the spot the difference puzzle in a Highlights magazine. However, two things jumped out to me.

The first is where Slater’s hands are set as he plants his front foot. Slater has lowered his hands while he waits for a pitch. Here’s Slater as he readies himself in 2018. His hands are above his eyes.

Here is again waiting for a pitch in Monday’s game. This time, his hands are level with his letters.

Where a batter sets their hands before the pitcher goes into their motion is less important than where their hands are when they begin their swing. Still, it’s a clear indication of what Slater is trying to do which is prevent himself from swinging down on the ball.

Here, we can see where Slater used to place his hands the moment before he began his swing.

His hands are high, his elbow’s up. He looks an awful lot like MLB logo. But he has one route to get to the ball: down.

Here’s Slater again before he hit the home run in Monday’s game.

It’s a slight difference, but his hands are a little lower and a little further back. From here, he can get the barrel up through the zone and get the ball in the air.

Second, Slater has altered his stride. In 2018, he had a dramatic leg kick and a long stride which isn’t necessarily a bad thing. Cody Bellinger is all stride, and he seems to be doing all right for himself. But something that Slater talked about with Doug was making sure his hips were firing right. He’s still striding to the ball, but he’s not bringing himself back before he does it. Perhaps eliminating that movement is allowing him to focus on turning his hips or perhaps it has allowed him to get lower, create more torque and whatnot.

The early returns on Slater’s new swing have been encouraging. We’ll have to see if his newfound success can continue, but an Austin Slater who doesn’t just live on the ground is an exciting player.