Finding the root of Corbin Burnes’ early home run problem

In Corbin Burnes’ entire minor league career, he gave up 11 home runs in 260 innings.

In his first 14+ innings in a Major League starting rotation, he’s given up 9 home runs.

Part of that is luck — the 3 home runs he surrendered in his start against the Chicago Cubs barely cleared the fences at Miller Park, and his HR/FB rate is still an absurdly high 64.3%. But part of that is also poor execution.

After Burnes’ first start, which managed to be both electric and head-scratching with 12 strikeouts and 3 home runs allowed, Fangraphs took a look at Burnes’ spin rate in that outing. The basic takeaway: high-spin fastballs like Burnes’ are almost impossible to hit when they’re high in the zone, and incredibly easy to hit far when they’re low in the zone.

That’s a pattern that largely continued in his following starts, including Friday night in Los Angeles against the Dodgers.

Of the 9 home runs Burnes has allowed this year, 8 have come on fastballs, according to Baseball Savant — 7 four-seamers and one two-seamer that Corey Seager took opposite field on Friday night. All but 3 of the home runs Burnes has allowed could be considered in the middle or lower half of the strike zone:

Courtesy: Baseball Savant

It doesn’t help that the teams that Burnes has faced in his first 3 Major League starts are likely 3 of the best 5 offenses in the National League in St. Louis, Chicago and Los Angeles. It’s one thing to make those mistake pitches, it’s another to make them against the likes of Matt Carpenter, Paul Goldschmidt, Javier Baez, Corey Seager, Cody Bellinger and Joc Pederson. Those are all hitters that won’t miss when a pitch is left in the middle of the zone.

Needless to say, Manny Pina and Yasmani Grandal haven’t been calling for those locations, but whether it’s part of the game plan created by the coaching staff or just what Yasmani Grandal is calling as he continues to work on getting familiar with a new pitching staff, a fastball-heavy approach early in the season may also be playing a role.

Burnes has used his fastball more than 2/3 of the time this year, up significantly from the 58.8% of the time he used it out of the bullpen last season. The usage of his slider -- seen as one of his stronger pitches as he came up through the minors -- has dropped from 34.3% last year to 22.3% this year.

That’s not quite Freddy Peralta levels of fastball usage, but when an opponent has a 2-in-3 shot of guessing right on a pitch and knows you’ve been missing in the middle of the zone, those pitches are going to get hit hard — like the 110 mph Cody Bellinger’s home run was measured off the bat Friday night.

Of course, which pitches are being called are only part of the equation. Peralta has shown if you can add enough movement or deception and locate the fastball, you can get away with that kind of rate, even as a starting pitcher. The problem Burnes (and Peralta, in his poor starts this year) has had is not being able to hit his spots regardless of who’s behind the plate.

At this point, it’s not just that Burnes isn’t hitting his spots with a pitch he’s throwing some two-thirds of the time — it’s by how much he’s missing.

This is an imperfect exercise due to camera angles not being centered and a few other factors (including trying to conceal location with runners on second base), but here’s a look at where the catcher set up vs. where Burnes ended up putting the ball on the home runs he’s allowed on fastballs:

On all three home runs surrendered against the Cardinals, Pina tried to get Burnes to go low and away. While Burnes’ fastball is better up in the top half of the zone, that’s hardly a bad strategy — especially against guys like Carpenter and Goldschmidt, who can hurt you just about anywhere else.

Against the Cubs, Grandal tried to bust Jason Heyward inside. Burnes missed up against Heyward, who judging by his swing, was selling out on a high fastball and was just lucky enough to see one. Normally, this wouldn’t be a bad pitch for Burnes, but Heyward just happened to guess right and was able to barely get it into the picnic area in right field. Facing Victor Caratini, Grandal had to try to conceal his location call with Heyward on second base, but appears to be setting up low and a little away, only for the pitch to end up middle-in.

Friday night’s start in LA saw a combination of a couple of issues noted above — the Corey Seager home run came on a pitch called low and away that ended up more middle-away, a pitch to Cody Bellinger ended up right in his pull zone (similar to the Goldschmidt home run), and the Joc Pederson home run is a near duplicate of the Heyward homer.

We know Burnes is capable of burning off a corner for a called strike — we’ve seen it both at times this year as well as last season, when he was coming out of the bullpen — so it isn’t really a question of if Burnes can show enough command to be a starter. That’s why Counsell and the organization is willing to be patient with Burnes as he navigates his first few career starts against some of the league’s best teams.

This type of adversity is also why the team has said it’s time to see what he has to offer as a starting pitcher, and why we won’t be seeing him moved back to the bullpen this year, regardless of what happens. Being a starting pitcher involves making a ton of adjustments as the season goes on and working yourself out of jams as they appear, and it’s time for him to learn by being in those situations.

If there’s good news with this early-season home run barrage, it’s that he’s otherwise been pitching decently well -- he’s striking guys out at a high rate, and he isn’t walking very many, which means about half of the home runs he’s surrendered have only been solo shots.

After Friday night’s game, manager Craig Counsell said Burnes will start again in 5 days’ time. He also acknowledged that Burnes needs to iron out his location problems:

“I’m not worried about him rebounding; I’m not worried about that at all. At this level, the mistakes on the fastball are hurting him. He’s paying the price. That’s the thing we have to evaluate and make sure we’re doing a good-enough job with.”

Corbin Burnes still has work to do, especially if the ball really has been changed this year to fly out of the park more easily. Whether that’s figuring out what’s going wrong mechanically or switching up his pitch selection and sequencing to use the slider more remains to be seen, but he’ll be faced with another challenge in his next start when he faces a team for a second time in the Cardinals.

Statistics courtesy of Fangraphs and Baseball Savant