Boston Red Sox First Baseman Triston Casas Undergoes Successful Season-Ending Surgery

Triston Casas had his left patellar tendon surgically repaired on Sunday, officially knocking the Boston Red Sox first baseman out for the rest of 2025.

Boston, Massachusetts, USA; Boston Red Sox first baseman Triston Casas (36) runs past Minnesota Twins first baseman Ty France (13) during the second inning at Fenway Park. | Eric Canha-Imagn Images

Boston Red Sox first baseman Triston Casas has undergone a successful left patellar tendon repair procedure, the team announced Sunday afternoon.

Casas suffered the knee injury Friday night, falling to the ground after beating out the throw on an infield single. He was placed on a stretcher and carted off the field at Fenway Park, then sent straight to a hospital for further evaluation.

The diagnosis of a ruptured patellar tendon came in Saturday, and the surgery was completed Sunday. Dr. Eric Berkson performed the procedure at Massachusetts General Hospital.

Casas is set to miss the rest of the 2025 season, at least, recovering from the surgery.

1B Triston Casas today underwent a successful left patellar tendon repair. The procedure was performed by Dr. Eric Berkson at Massachusetts General Hospital.

— Red Sox (@RedSox) May 4, 2025

The 25-year-old was batting .182 with three home runs, 11 RBIs, a .580 OPS and a -0.8 WAR through 29 games this year. He was limited to 63 games in 2024 due to a rib and abdominal injury.

In 2023, Casas finished third in AL Rookie of the Year voting, batting .263 with 24 home runs, 65 RBIs, an .856 OPS and a 2.2 WAR.

The Red Sox do not have a clear internal option to take over for Casas in either the short or long term, putting the team in a precarious situation just one month into the season. As for Casas, his long road to recovery has officially begun, although it remains to be seen just how long it will take for him to return to the big league lineup.

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