Astros: Corbin Martin undergoes Tommy John surgery

Astros pitcher Corbin Martin underwent Tommy John surgery on Wednesday and will miss the rest of the season.

The Astros’ starting pitching issues took another hit on Wednesday when top prospect Corbin Martin underwent Tommy John surgery. Martin will miss the remainder of this season and a chunk of next season as well, setting back the timetable for his emergence as a quality MLB pitcher.

Martin is ranked as the team’s fourth-best prospect by MLB.com, noting he has the arsenal and the delivery to be effective deep into ballgames. He made his major league debut on May 12 by fanning nine Rangers hitters, but struggled in four subsequent starts.

Martin becomes the latest young Astros hurler to go under the knife for the infamous operation to replace a torn ulnar collateral ligament in the elbow. Lance McCullers Jr. and Francis Martes have also undergone the procedure in the past year.

What This Means for Martin and the Astros

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For Martin, it means there’s a good chance he won’t find himself in a major league rotation until 2021. His 2019 season is finished, and he most likely won’t be ready for the start of the 2020 season. A typical timeline would have him returning to action at some point in the second half of next season, but it would be a surprise to see him go straight into the big league rotation.

He’ll need some rehab time in the minors to build his arm strength back up and to get accustomed to facing live hitters again. Further, the team will undoubtedly be limiting his innings upon his return. So if he were to return to the big leagues next year, it would likely be in a relief role down the stretch. If all goes well, he could compete for a rotation spot in 2021.

For the Astros, this adds additional uncertainty to the outlook for their starting rotation next season. With Gerrit Cole, Wade Miley and Collin McHugh set to reach free agency after this season, only Justin Verlander, Brad Peacock and McCullers look like locks for the rotation. Plus, McCullers may be on an innings limit next year, which would be his first campaign following his surgery.

Martin’s injury, combined with the inability of other young pitchers to make a difference at the big league level this season, could force the Astros to acquire additional pitching either at the trade deadline or in the offseason. It could also encourage them to go deep into the bidding for Cole and Miley, which they may or may not have been inclined to do otherwise.