A long time ago, right around when the Dodgers moved from Brooklyn to Los Angeles, Vin Scully had an offer to stay in New York to call Yankees games. He declined obviously, but if he hadn't, this probably wouldn't have been as neat.
Here is Scully (a Hall of Famer) calling Mariano Rivera's (a future Hall of Famer) save against the Dodgers on Wednesday night as the Yankees made a rare interleague trip to Dodger Stadium:
Rumor has it Rivera ranks quite well in that "relatively new stat" called WHIP. What a fun inning.