They dont want to waste his outing. Say he pitches 4 innings and it gets rained out until tomorrow or a hour or two delay. He wont be able to come back and pitch. It is a pretty smart move, IMO. It just didnt work out for him tonight.
Which is exactly what ended up happening...
Kennedy threw 3 innings...and did not look very good. Girardi knew all along that he was going to use him at some point...if he's not going to start his starter...then he should skip him altogether...
Greinke is a relatively young kid...and Hillman stuck with him...and he dealt a real nice game.
I have always played listed pitchers in bases...but now I am finding that I have to check the forecast...and then just box the pitcher for the side I am on, with certain managers.