Detroit Tigers right-hander Jack Flaherty has a 4.61 ERA through eight starts in the 2025 season, a significant regression from his 2.95 ERA over 18 starts for the Tigers in 2024. The 29-year-old is struggling with his four-seam fastball.
The problem: Flaherty isn’t missing bats with his fastball anymore.
The result: Hitters are making more contact and doing more damage.
“We want him to work on everything,” Tigers manager A.J. Hinch said of his team’s No. 2 starter. “This isn’t really who he is. It’s who he’s been for a couple of starts. This is how the big leagues can be if you don’t execute.”
His four-seam fastball whiff rate has dropped from 23.9% in 2024 to 11% in 2025, including zero whiffs on eight swings May 10 in the Tigers’ 10-3 loss to the Texas Rangers. The velocity, movement and spin efficiency remain virtually unchanged from last season, but the fastball is suddenly inconsistent.
So, why is this happening?
The drop-off in effectiveness stems from Flaherty’s continued struggle to consistently repeat the delivery mechanics that fueled his breakthrough success last season.
He’s still searching for a permanent solution, even three months after reporting to spring training.
“I’m still feeling through some things with delivery and timing, so just trying to find where I can repeat it over and over again,” Flaherty said. “I’m trying to transfer things over from bullpens to starts. One pitch will be good, and then the next one, maybe not so great. I’m trying to be more consistent.”
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The Tigers noticed mechanical changes in Flaherty’s delivery after trading him July 30 to the Los Angeles Dodgers for two prospects at the 2024 trade deadline, which coincided with a drop in strikeouts and a rise in walks.
President of baseball operations Scott Harris pinpointed the issue with Flaherty’s delivery.
“I thought his arm action was a little bit more abbreviated,” Harris said Feb. 7, after re-signing Flaherty in free agency. “Oftentimes, that’s a mechanical issue. I thought he had a little bit more arm speed earlier I the year with us.
“One thing about Jack is that he’s a freak athlete. He makes adjustments so quickly. I don’t think that’s going to be an issue for us at all.”
The Tigers re-signed Flaherty to a two-year, $35 million contract as spring training approached, only after other teams passed on him in free agency. The deal includes a $10 million escalator clause that boost the total value to $45 million if he makes 15 starts in 2025. He already has eight starts under his belt, so he needs just seven more to trigger the bonus.
But his last three outings have been underwhelming.
“I’m trying to get everything in sync right now,” Flaherty said.
Over those three starts, Flaherty has an 8.56 ERA — allowing four runs in five innings April 28 against the Houston Astros, five runs (four earned runs) in 5⅔ innings May 3 against the Los Angeles Angels and five runs in three innings May 10 against the Rangers.
Facing the Rangers, Flaherty allowed four home runs — all to left-handed hitters — for the first time in his nine-year MLB career, spanning 167 games.
“I think you’re surprised any time you only last three innings in a game,” Flaherty said.
To bounce back, Flaherty needs to rediscover the mechanics for his delivery that made him successful, learn to repeat those mechanics consistently in game situations and sharpen the execution of his pitches.
The fastball, in particular, must improve.
“I’m not worried about it,” Flaherty said. “I won’t stop until I figure it out.”
Contact Evan Petzold at epetzold@freepress.com or follow him @EvanPetzold.
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This article originally appeared on Detroit Free Press: Detroit Tigers’ Jack Flaherty explains struggles: ‘I won’t stop until I figure it out’
Reporting by Evan Petzold, Detroit Free Press / Detroit Free Press
USA TODAY Network via Reuters Connect
