I lied. I'm also gonna talk about it.
Bottom line: I think Rob is correct: Joe Girardi did the right thing by not using Mariano last night in a (superficially) close game. Perhaps, perhaps, there's an argument if the Yankees were only down one run, and certainly he should have and would have been used if the Yanks had been tied or ahead.
But down two runs in the ninth inning is not a terribly high leverage situation. In fact, it's a very low leverage situation (see here). The Yanks have games today and tomorrow. In my opinion, it's worth more having a rested Mo today and tomorrow than it is to try and keep a two run deficit at two runs, especially when your reward for doing so will just be more Cliff Lee.