Updated: Mariano Rivera tears ACL; David Robertson and Rafael Soriano loom as possible replacements

The 2012 fantasy season already had "Year of the Closing Change" written all over it, but the biggest bombshell dropped Thursday night in Kansas City.

Mariano Rivera, widely acknowledged as the greatest closer of all time, tore an ACL while shagging batting-practice flies at Kauffman Stadium. He's going to be examined in New York on Friday, but it's just about certain that he's done for 2012. It's also possible his career could be over; Rivera, after all, is 42 years old.

For many roto players, it's impossible to imagine the game without Rivera: he's been a dominant closer for 15-plus seasons. Rivera broke in with the Yankees in 1995, mainly as an ineffective starter. He shifted to the bullpen full-time the next year and was a lock-down setup man (2.09 ERA, 0.99 WHIP) for the eventual World Champs. Rivera stepped into the closer's chair the following season (recording 43 saves) and the rest is history. He's collected a MLB-record 608 handshakes, all of them for the Yankees.

Legends aren't easily replaced, but the Yankees do have a couple of viable options for the ninth inning. David Robertson has been the primary setup man in The Bronx the last two years and his numbers leap off the page. Last year he fashioned a 1.08 ERA and 1.13 WHIP (along with 100 punchouts in 66.2 innings), and he's yet to allow a run over 11 electric innings this season (7 H, 3 BB, 18 K). I can't see any reason why Robertson wouldn't be a dominant closer, and he's the first name I'd target if you still have that option. His ownership level has spiked from 37 percent to 56 percent since the Rivera news initially broke.

Just because Robertson is the best holdover in the bullpen doesn't necessarily mean he'll step into the ninth inning, of course. The theme of the closer varies from city to city, manager to manager. With that in mind, we also have to consider veteran Rafael Soriano. The high-priced righty has a couple of wins on the young season and a 2.00 ERA, but the deeper you look, the less impressed you become. Soriano has somehow skated around a 1.89 WHIP, and he's walked six batters in nine innings. He was hurt for much of 2011; when on the field, he turned in mediocre results (4.12/1.30).

Bottom line, until manager Joe Girardi hands us the new bullpen blueprint, we can only speculate. Soriano worked in Thursday's loss, pitching the bottom of the eighth with the Yankees down a run; that at least suggests that Robertson was being saved for a possible save chance. But that doesn't mean Girardi is married to Robertson as the next closer moving forward, albeit that seems like such a logical move to most roto players.

If you roster both Robertson and Soriano as your speculation plays, well done. If you only had one shot at it and you landed Robertson, I think you made the right move. But nothing really matters until Girardi comes to a decision and notifies the masses.

Feel free to discuss the New York bullpen – past, present and future – in the comments. I grew up as a diehard Boston fan and that's never going to be shaken out of me, but as a general baseball fan, I'm sad tonight. If you care about this game and the people in it, you have a ton of respect for No. 42 in pinstripes. Here's to a quick recovery, Mo, and to hopefully going out on your own terms, down the road. The ninth inning won't be the same without you.