New York Yankees closer Mariano Rivera injured himself during warm-ups on Thursday before a game against the Kansas CIty Royals. He was driven off the field and taken to a nearby hospital for an MRI.

Jeff Passan of Yahoo! Sports reported that Rivera suffered a torn ACL. Daniel Barbarisi of the Wall Street Journal clarified that the MRI results and the doctors at Kansas City believe that the diagnosis is an ACL tear. The general assumption at the moment is that Rivera's season is over.

A short time later, the Yankees officially announced that Rivera had suffered a torn ACL in his right knee.

Mark Feinsand of the New York Daily News had some comments from Yankees manager Joe Girardi regarding the injury.

"It appears he has a torn ACL ... If that's what it is, it's pretty much as bad as it gets. This is bad. Good teams find a way to overcome things.

"There are a lot of things in life that make you feel hopeless. Injuries are not one of them."

Girardi said he would sleep on who will take over as closer. "We have two guys that are very capable. It's not what you want, but it's not season over. ... You have to find a way to overcome it."

Yankees fans have to be pretty worried about Rivera potentially being out for the season, even if there are solid options for a new closer in-house.

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