The Abbott and Costello "Who's on First?" standup routine is one of the more famous baseball comedy routines in history. On Thursday's episode of Late Night with Jimmy Fallon, the routine was reprised by Fallon, along with cameo appearances from Billy Crystal and Jerry Seinfeld (playing the roles of "who" and "I don't know" respectively).
It's a classic routine, and while nothing can top the original as performed by Abbott and Costello, Fallon did a solid job at paying tribute to the original spirit of the act whle also adding a bit of his own spin with the introduction of the players being spoken of. I'm not a fan of his comedy at all, but I'll give him and his staff a B+ for this skit, even if the appearances by Crystal and Seinfeld took a bit away from the performance with the rousing ovations they got from the studio audience.