Cardinals’ Cooper Hjerpe Undergoes Tommy John Surgery

The Cardinals announced that pitching prospect Cooper Hjerpe has undergone Tommy John surgery. The left-hander will miss the entire 2025 season and won’t be expected back until midway through the 2026 campaign.

Hjerpe, 24, is one of the club’s top pitching prospects. He was selected in the first round, 22nd overall, in the 2022 draft. He received a signing bonus of just under $3.2MM. He has since posted some intriguing minor league numbers, with plenty of strikeouts though also lots of walks. He logged 93 1/3 innings over 2023 and 2024, splitting his time between High-A and Double-A. He allowed 3.37 earned runs per nine, punching out 32.8% of batters faced but also giving out free passes at a 13.7% clip.

His elbow health, or lack thereof, has been a part of the trajectory in that time. He required surgery to remove loose bodies from that elbow in 2023, limiting him to just eight starts that year. In 2024, his final start of the season was on July 2, with an elbow injury shutting him down from then on.

Clubs and pitchers generally prefer to take non-surgical approaches to injuries for as long as they can, as going under the knife is such a lengthy time commitment and there are no guarantees that a player will return to 100% effectiveness afterwards. But in this case, it could be avoided no longer, so Hjerpe is now going to be on the shelf for a while.

Despite the limited workload, Hjerpe is well regarded. Baseball America currently lists him as the #7 prospect in the Cards’ system, highlighting his unique sidearm delivery as he throws an arsenal that includes a fastball, curveball, cutter and changeup. Back in May of last year, Eric Longenhagen and Travis Ice of FanGraphs had him in the #5 spot.

If Hjerpe were healthy here in 2025, he likely would have returned to Double-A and could have pushed for a Triple-A promotion at some point during the season. All that will have to be kicked down the road now.

Some interesting decision points will come this winter, as Hjerpe will be eligible for the Rule 5 draft in December. The Cards will have to decide if it’s worth giving him a 40-man spot by the Rule 5 protection deadline in November. He’s obviously an important prospect in the system but has a limited track record and will still be rehabbing at that time. However, grabbing an injured pitcher in the Rule 5 isn’t unprecedented. In the most recent iteration, the Blue Jays took Angel Bastardo from the Red Sox while the Rays grabbed Nate Lavender from the Mets. Both of those pitchers underwent Tommy John surgeries last summer and could potentially return later this year.

Photo courtesy of Jim Rassol, Imagn Images