The Yankees lost Mariano Rivera for the season when he tore his ACL shagging fly balls during batting practice two days ago. He says he will return to pitch next season, though the team still needs to replace him for the remainder of 2012.
Rivera, 42, is the greatest reliever in baseball history and even at his advanced age, the Yankees will be unable to find someone who can match his brilliance. Setup man David Robertson has emerged as one of the game's best non-closing relievers over the last year, pitching to a 0.92 ERA with 121 strikeouts in 78 2/3 innings since the start of last season. He seems like the obvious choice to replace Rivera, at least initially, but he's not the only option.
Ownership overruled GM Brian Cashman two offseasons ago to sign Rafael Soriano, the former All-Star closer with the Rays who became a setup man in New York. He missed time with an elbow issue last year and has pitched to a 3.72 ERA with 8.2 K/9 in 48 1/3 innings since signing with the Yankees. Although he's been outpitched by Robertson, the team could prefer his ninth inning experience in Rivera's stead. His salary ($11MM in 2012) could also be a factor.
Yesterday we heard that the Yankees will not aggressively pursue a reliever, but a trade can never really be ruled out. Closers like Huston Street, Brandon League, Brett Myers, and Jonathan Broxton could be available at the trade deadline, though that is just my speculation.