On his show last night, Jimmy Fallon re-created a comedy classic with a new take on Abbott and Costello’s Who’s On First? routine where we finally get to meet the team’s first baseman Who, second baseman What, and third baseman I Don’t Know. (you can watch the original skit below the new one.) Joining Fallon onstage are Billy Crystal and Jerry Seinfeld (as well as Fallon announcer Steve Higgins as Costello and Fallon head writer A.D. Miles as What.)