Pittsburgh, PA -- Pittsburgh Pirates second baseman Jose Castillo, who was placed on the 15-day disabled list Monday, will now miss the rest of the season with an injured knee.

Castillo had an MRI Tuesday that showed a torn medial collateral ligament in his left knee, but he will not require surgery.

Castillo collided with the Cardinals' Hector Luna, who slid hard into second in an attempt to break up a play, in Pittsburgh's 3-1 defeat to St. Louis on Monday. The second baseman had to be helped off the field by the Pirates' training staff.

Castillo put together a strong second season in the majors. Through 101 games, he batted .268 with 11 homers and 53 RBI.

Ty Wigginton, Pittsburgh's starting third baseman during the early part of this year, was recalled from Triple-A Indianapolis to take the roster spot. He drove in three runs Tuesday in the Pirates 10-0 win.