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Yankees' closer Rivera suffers potentially career-ending injury

AP

In this image taken from video, New York Yankees' Mariano Rivera, center, grimaces after twisting his right knee shagging fly balls during batting practice before a baseball game with the Kansas City Royals, Thursday, May 3, 2012, in Kansas City, Mo.

Manager Joe Girardi revealed the severity of the injury after the game. Royals team doctor Vincent Key diagnosed a torn ACL after looking at the MRI.

"This is bad, there's no question about it," Girardi. "

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