The Cardinals have announced that pitching prospect Cooper Hjerpe has undergone Tommy John surgery. As a result, the left-hander will be sidelined for the entire 2025 season and isn’t expected to return until sometime in the middle of 2026.
Hjerpe, 24, is considered one of the organization’s top young arms. He was selected 22nd overall in the first round of the 2022 draft and signed for nearly $3.2 million. In the minors, he’s shown promise with strong strikeout numbers, though control has been an issue. Over 2023 and 2024, he pitched a total of 93 1/3 innings between High-A and Double-A, posting a 3.37 ERA. He struck out 32.8% of hitters but also walked 13.7%.
Injuries have already been a part of his career path. He had elbow surgery in 2023 to remove loose bodies, limiting him to eight starts that year. His final outing in 2024 came on July 2, after which elbow trouble again put him out of action.
Teams typically try to avoid surgery for as long as possible due to the long recovery and uncertain outcomes, but in Hjerpe’s case, surgery became necessary.
Despite the limited time on the mound, Hjerpe remains a highly regarded prospect. Baseball America ranks him seventh in the Cardinals’ system, noting his unusual sidearm delivery and mix of fastball, curveball, cutter, and changeup. Last May, FanGraphs placed him fifth in their rankings.
Had he stayed healthy in 2025, Hjerpe likely would have returned to Double-A and possibly moved up to Triple-A. That progression will now be delayed.
The Cardinals will face a tough decision this offseason, as Hjerpe becomes eligible for the Rule 5 draft in December. They’ll need to determine whether to protect him with a 40-man roster spot by November’s deadline. While he has limited professional experience and will still be in rehab, teams have taken injured pitchers in past Rule 5 drafts—like the Blue Jays with Angel Bastardo and the Rays with Nate Lavender, both of whom had Tommy John surgery last summer and could return later this year.
