PHOENIX — Arizona Diamondbacks pitching coach Brent Strom worked with rookie Tommy Henry in the bullpen Saturday, and the southpaw walked away with improved spin rate on his breaking balls.

Strom visited with reporters after the session, and said he noticed Henry gripped his slider and curveball on his fingertips.

“Really good breaking ball pitchers that I’ve had a chance to be around … they hold the ball a lot deeper in their hand,” Strom said.

Strom had Henry grip the ball much deeper in his left hand, and they saw results.

Tommy Henry’s first Major League strikeout! pic.twitter.com/mImY7VRJPD

— Arizona Diamondbacks (@Dbacks) August 3, 2022

The coach said TrackMan data disclosed Henry’s spin rate went up after the change, and he felt more power with the two pitches.

Henry made his MLB debut Wednesday in Cleveland. The 23-year-old had a 3.83 ERA in 20 starts with Triple-A Reno this year and is Arizona’s No. 12 prospect on MLB Pipeline.

The southpaw attacked primarily with his fastball but went to the slider as his primary offspeed pitch.

Henry handled himself with four innings of one-run ball before surrendering a three-run home run in the fifth.

Strom liked Henry’s composure during his debut, an outing in which he finished with four runs in five innings. But, Strom noticed some of his pitches “didn’t have the bite” he expected. Henry got 15 swings on sliders but only two whiffs.

“I just decided to make a jump at it and see if it worked,” Strom said. “He seems to like it. All you can do is try and if it doesn’t work, then you go to a different thing. But he seemed to like it today. So that’s the kind of stuff that I live for, really, to see these kids improve.”

Strom noted that Henry is not the only D-backs arm who altered a grip recently.

The veteran coach had Zac Gallen loosen his changeup grip since the pitch was not getting hitters on their front foot as much as it should have. Strom called it a page out of Greg Maddux’s book.

“As the season goes on, you’re always looking to tweak things, very rarely do you just stay the course,” Strom said.

Tommy Henry is dealing early 😤

He’s recorded 4️⃣ strikeouts through 2️⃣ innings. pic.twitter.com/xRSNxAkILE

— Reno Aces (@Aces) July 30, 2022

Strom noted that the Guardians provided a challenge for Henry to make his debut as a team with speed that puts the ball in play.

He tried to hype Henry up pregame by playing the University of Michigan’s, where the rookie went to college, fight song.

Henry’s next crack is scheduled on Tuesday against the Pittsburgh Pirates, who visit the D-backs Monday-Thursday.

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