Mariano Rivera Tears ACL

New York Yankees closer Mariano Rivera tore the ACL in his right knee yesterday while trying to catch a fly ball during practice in Kansas City prior to last night's game against the Royals. Rivera could be out for the rest of the season, possibly a career ending injury.

Let's just say right off the bat that this is the biggest challenge the Yankees have faced in more than 15 years. Rivera has been the Yankees closer since 1997. The Yankees have missed one post-season in his entire big league career. Rivera has 608 career saves, the most in MLB history. The 42-year old Panamanian has been his usual self. At the time of the injury, he was 1-1 with a 2.16 ERA and five saves.

Needless to say, who will the Yankees put out there in the ninth? Rafael Soriano did save 45 games for the Tampa Bay Rays in 2010. Soriano struggled in 2011 and although he has pitched better in 2012 his walk totals are a little scary (six walks in nine innings). Being the closer might be shot in the arm he needs.

David Robertson has pitched well as an eighth inning set up man but is untested as a closer. Then again Rivera pitched well as an eighth inning set up man but was untested as a closer after John Wetteland went to Texas after the 1996 season. Robertson hasn't given up a run in 11 innings pitched this season and has 18 strikeouts to boot. But eighth inning success doesn't always translate into the ninth and Robertson is an unknown quantity in the ninth as is Phil Hughes who has struggled to regain his form of 2010 when he won 18 games. Hughes has had success in the bullpen as an eighth inning set up man during the Yankees World Series championship season of 2009.

The dark horse in all of this is Joba Chamberlain who dislocated his right ankle while jumping on a trampoline late in spring training. He just got put on the 60-Day Disabled List but could be back late in the season. If Soriano, Robertson and Hughes don't pan out and they don't trade for a closer then Chamberlain is an option.

In the grand scheme of things, losing Mariano Rivera is bad for baseball. He is a class act on and off the field and even Red Sox fans cheer for him. That would never happen with Jeter or A-Rod. Mariano Rivera is in a league of his own and it would be shame if this was the way his storied career ended.

UPDATE: Rivera, who had been pondering retirement after this season, vows to return in 2013.