(AP) -- KANSAS CITY, Mo. (AP) - Mariano Rivera tore a ligament in his right knee before the New York Yankees lost 4-3 to the Kansas City Royals on Thursday night.

The 42-year-old right-hander was carted off the field after twisting his right knee shagging fly balls during batting practice.

Manager Joe Girardi revealed the severity of the injury after the game.

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