KANSAS CITY, Mo. -- Mariano Rivera tore the anterior cruciate ligament in his right knee Thursday night and is out for the season. It is a possible career-ending injury for the New York Yankees' 42-year-old closer.
Rivera, the all-time saves leader, suffered the injury while shagging balls in center field during batting practice before the Yankees' 4-3 loss to the Kansas City Royals on Thursday.
"I thought it wasn't that bad, but it's torn," Rivera said after the loss. "Have to fix it."
Rivera said he has shagged fly balls throughout his career and it helps keep him in shape.
Rivera, who is in the final year of his contract, had hinted 2012 could be his finale. He did not say Thursday whether he has indeed thrown his last pitch.
"At this point, I don't know," Rivera said. "(I'm) going to have to face this first. It all depends on how the rehab is going to happen, and from there we'll see."
Rivera went down in agony on the warning track while chasing after a fly ball hit by Jayson Nix. Manager Joe Girardi and bullpen coach Mike Harkey picked up Rivera, who was in obvious pain, and carried him to a cart, which took him off the field.
The preliminary diagnosis was a twisted right knee. Rivera was examined by Dr. Joe Noland, a Royals associate physician, and the Yankees training staff. Rivera was taken to KU MedWest Hospital for an MRI, which revealed the tear.
"It's obviously a huge loss," Yankees third baseman Alex Rodriguez said. "No one is going to feel for sorry for us. We've got five months to play. It's hard to talk about it tonight. Guys have got to pick it up. Mo is Mo."
Could the injury have been prevented if Rivera was not allowed to chase fly balls in batting practice?
"You can fall off the curb or down stairs and get hurt," Girardi said.
The seriousness of the injury hit the Yankees hard.
"It's not what you want, but it's not season over," Girardi said. "This is bad. There's no question about it. This is not what you want to come to Kansas City to hear."
There has never been another closer like Rivera, who has 608 saves. He has not been on the disabled list since 2003, when he had a strained right groin. After blowing a save in the season opener at Tampa Bay, Rivera had tossed eight scoreless innings and was 5-for-5 in save opportunities.
Rivera had 27 consecutive saves against the Royals. He had not blown a save against them in 13 years -- since May 2, 1999.
David Robertson, who has not allowed in run in his past 24 innings -- dating to Sept. 1, 2011 -- will serve as the Yankees' closer in Rivera's absence. He has three big-league saves.