Entering pro ball, Ben Jacobs was seen as a promising left-hander with a track record of racking up strikeouts in college but with questions about how it would translate against better competition.
With a pair of above-average offerings but nothing plus, could the Tigers' 2025 third-rounder become an effective big league starter?
Four months into his first campaign, the signs are pointing to yes. Jacobs' star has risen in Detroit's farm system to the point that the southpaw now ranks as the club's No. 5 prospect and top pitching prospect.
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The California native has been one of the top strikeout artists in the Minors this season, with 89 in 61 1/3 innings between Single-A Lakeland and High-A West Michigan. His 34.2 percent K rate ranks 16th among Minor Leaguers with at least 60 innings this season -- and is higher than his 33 percent mark at UCLA and Arizona State.
Key to his success has been a three-pitch mix that is playing better than expected and generates plenty of swing-and-miss. His fastball has added a tick of velocity since his days with the Sun Devils and plays up at the top of the zone because of his lower release point and the ride he can impart on the pitch. Despite throwing it at a 61 percent clip and topping out at 96 mph, Jacobs still gets opponents to whiff on a third of his heaters.
The 22-year-old's secondary offerings have been especially dangerous. His slider and changeup both sit in the low 80s and are picking up swings-and-misses at a 41 percent rate. The changeup has been particularly devastating, causing hitters to chase 44 percent of the time, thanks to good separation from his fastball.
The armside movement on the cambio -- especially playing off the harder fastball -- has enabled Jacobs to have a fairly pronounced reverse split. He's holding righties to a .212/.303/.308 slash line while fellow lefties are hitting .243/.341/.543. He had essentially no platoon split his junior year at ASU.
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Jacobs began his pro career in the Florida State League -- like many college pitchers brought into the Detroit system -- to take advantage of the warmer weather, but it was quickly apparent that he was too advanced for Single-A. He gave up just two runs in 16 2/3 innings while striking out 24 before making his way to the Midwest League.
High-A has been more of a challenge as he carries a 6.04 ERA through 12 outings (11 starts), but the keys to success are apparent. Jacobs' stuff is playing against higher competition -- his 33 percent strikeout rate ranks eighth on the circuit (min. 40 IP) -- and he's been mixing in an upper-70s curveball against lefties.
Jacobs isn't the most physical starter at 6-foot-1 and has had fringy control dating back to college that could limit his ceiling. But his improvements since entering pro ball are notable and have solidified him as one of the most important arms to watch in the Tigers' system.