If not Tanaka, who?

The Yankees' battered rotation took the biggest hit of all Wednesday when RHP Masahiro Tanaka went on the 15-day disabled list because of a sore elbow.
Tanaka leads the majors with 12 wins. He has a 2.51 ERA. He didn't give up more than three earnies in any of his first 16 starts, but surrendered four July 3 and five more Tuesday night. That performance led to a trip back to New York for an MRI exam.
The first question is how long he might be out? With a 4-day All-Star break coming up, he would likely miss just two starts before the minimum 15 days when he could return.
But if the injury is more serious than a 15-day ailment, the Yankees could be in an awful place with their rotation.
Without the ace, could New York count on RHP Brandon McCarthy, who brought a 3-10 record with him when he was traded from Arizona, to head the rotation? Or Hiroki Kuroda, whose second half last season was a train wreck? David Phelps? Rookie Chase Whitley?
Early candidates for the rotation -- LHP C.C. Sabathia and RHPs Ivan Nova and Michael Pineda -- are all on the 60-day DL.
The trouble isn't just at the top of the rotation, but all the way down to who would fill the No. 5 slot.
Could they move someone from the bullpen, such as LHP David Huff? Or RHP Bruce Billings, just brought up from Triple-A Scranton, where he was in the rotation? Other possibilities from Scranton could be Shane Greene or 35-year-old former outfielder Brian Gordon.
Among them, Billings, Greene and Gordon have a .500 record (13-13). In Triple-A.
The Yankees have been barely a .500 team even with Tanaka. Without him, .500 would look pretty good.