Corbin Carroll's Fastball Problem Leads to a Sophomore Slump

Teams are pounding Carroll with fastballs and so far he's not been able to consistently respond

May 4, 2024; Phoenix, Arizona, USA; Arizona Diamondbacks outfielder Corbin Carroll (7) hits a single against the San Diego Padres / Joe Camporeale-USA TODAY Sports

One of the key character traits of Diamondbacks General Manager Mike Hazen is that he always seems to have the ability to put events in their proper perspective. Such was the case on Wednesday while speaking on Arizona Sports 98.7 with Ron Wolfley and Luke Lapinski.

The topic turned to 2023 NL Rookie of the Year Corbin Carroll, who has been experiencing the dreaded sophomore slump. 50 games into the season he's batting .191/.275/.282 with just two home runs and 10 extra base hits overall.

There have been recent signs that he might be coming out of it over the last week as he's hit some balls hard. Rather than declare him "fixed" however, Hazen acknowledged that it needs to come more consistently.

"He obviously has gotten off to a tough start and he's one of our best players," Hazen said. "He's one of the pieces in our lineup, he's not the only piece, that we need to get going in a consistent meaningful way."

Over the last week Carroll has exactly one hit in each of his last five games, but four of those hits have been for extra bases including a double and three triples. Hazen cited this stretch, and a double he hit against the Dodgers on Tuesday night in particular, as an indication that things might be trending in the right direction.

"I think that is what we weren't seeing earlier in the season and is what makes me feel like things are starting to move in a direction that they need to move. He's smoking baseballs again. I think that is a good sign for when he gets going that it's all still there. It's all still inside and we just need to get it a little more consistently."

Does the Data Back Hazen Up? Yes, Somewhat.

In order to examine this properly we need to look at the quality of Carroll's contact recently and the expected statistics derived from that quality of contact and plate discipline. This can been found via the Statcast Search Tool at Baseball Savant.

Frequently when a player is struggling you might hear that he's been smoking the ball but hitting it right at people and getting unlucky. That has not been the case with Carroll, as can be seen in the table below. All of the expected outcomes of BA, OBP, and Slugging continue to be well below average, with one exception: Barrels.

A barrel is a ball struck with at least 98 MPH exit velocity and a launch angle between 26-30 degrees. These are the hardest struck baseballs at the optimum angles and create the best results. The Barrel per Batted Ball event number in the far right for the week of may 16-22 shows exactly what Hazen was talking about. A handful of hard struck balls.

Corbin Carroll Expected Stats and batted ball quality over last 4 weeks / Jack Sommers

The Fastball Problem

As anyone who watches Diamondbacks games on television can attest, the broadcast team of Steve Berthiaume and Bob Brenly have often lamented the fact that Carroll is getting consistently beat with fastballs, especially fastballs up and on the inner half of the plate.

When we examine Carroll's batting numbers against fastball we see a stunning trend. Over the first half of 2023 he was crushing fastballs. But starting from July 1st to the end of the season his production on fastballs dropped off dramatically.

Teams picked up on this and starting giving him a steady diet of heaters. In fact after seeing fastballs about 56% of the time during the regular season, that rate jumped to 72% in the postseason. Teams figured out that he was struggling with fastballs for some reason and began attacking him accordingly. That trend has continued into 2024.

Corbin Carroll against fastballs, all types / Jack Sommers

One thing about the dates that might jump out to a close follower of the team is that the drop off in power production against the fastball coincides with when he tweaked his surgically repaired shoulder in late June 2023.

After hitting 13 homers against fastballs in the first half of 2023, he has just three homers off a fastball since July 1st last year. Carroll has steadfastly maintained that he is not injured or experiencing any shoulder pain however.

Pundits, scouts, and "experts" from all around the league have weighed in with all sorts of analysis and breakdowns of his swing and mechanics. Carroll himself said that his bat path became too flat.

No matter the reason, if Carroll is to regain any semblance of the hitter he was over the first half of 2023 he must start punishing fastballs again. The swing that Hazen referenced in his interview was a indeed a fastball, on the outer part of the plate.

It's a small step in the right direction. As Hazen said, we need to see a lot more of that. His cautionary tone is warranted. There is still a ways to go before Carroll is back to the hitter he was in the first half of 2023.