The one pitcher that fans can stop talking about coming to the Bronx is Felix Hernandez. If he is ever traded, it will not be to the Yankees. In addition to other reasons, the payroll constraints the Yankees have over the next several seasons will make it difficult to add a contract similar to Felix's. Other pitchers that have been talked about: Matt Garza, Zack Grienke, Francisco Liriano and Ryan Dempster may or may not be realistic options. Grienke and Garza will want extensions the Yankees cannot commit to and it would not make sense to give up something of value for Dempster who will be a rental. Out of the list, only Liriano is controlable for the next couple of years. He may not, though, be worth what he is scheduled to make in arbitration.
So, if they decide to make a move, who should it be? The Yankees will not be penalized for adding payroll towards the end of this season. So while Dempster is a possibility because he is most likely to test free agency after the season. Other options include Jorge de la Rosa of the Rockies, who is currently injured. The cost for him will be minimal and they can work out de la Rosa's player option for 2013. They can possibly agree that he not exercise it. While the return of Carl Pavano is unlikely, perhaps the Athletics may look to get something for Bartolo Colon. I think a reunion is a possibility. Other pitchers that have not been talked about are Seattle's Kevin Millwood and Houston's Brett Myers. Myers is interesting because he is currently the Astros closer and could start until Pettitte returns, then help in the bullpen.
The biggest question is do the Yankees really need another SP? If they feel like they do, it should not be a top of the rotation guy since they have 5 solid starters once Pettitte returns.