WordNet
new ballgame
n. a particular situation that is radically different from the the preceding situation; "HDTV looks the same but it's really a whole new ballgame" [syn: ballgame]
Usage examples of "new ballgame".
What you two are looking at-well, I think you realize that's a whole new ballgame.
If they could read minds and do magic here in the DoOon Mode, it would be a new ballgame.