YES Network.com

New York Mets reliever Tim Byrdak has a torn anterior capsule in his left shoulder, and will be out indefinitely.

An MRI on Monday revealed the injury, and according to the team, a treatment plan has not been finalized, although surgery is a likely possibility; two of the Mets starters, Johan Santana and Chris Young, have both had surgery for the same injury, with Santana missing more than a year as a result.

The injury is also similar to the one that has kept fellow lefty specialist Pedro Feliciano sidelined for the duration of the two-year deal he signed with the Yankees prior to the 2011 season. Feliciano, who made 459 appearances for the Mets from 2002-2010, has not thrown a pitch since feeling shoulder soreness in Spring Training last year and having surgery to repair both a torn capsule and rotator cuff.

Byrdak, 38, is 2-2 with a 4.40 ERA this season and leads the Majors with 56 appearances. He last pitched on August 1, when he recorded his 17th hold of the season by facing one batter in the eighth inning of the Mets’ 2-1 win in San Francisco, and he was placed on the disabled list prior to Friday’s game in San Diego after reporting shoulder soreness.

To replace Byrdak, the Mets promoted lefty Garrett Olson from Triple-A Buffalo. Olson was 4-7 with a 4.56 ERA in 25 games (21 starts) at Buffalo, and last pitched in the Majors in April 2011 with Pittsburgh, allowing one earned run in 4 1/3 innings pitched over four appearances.

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