This is "SNL's" 34th season, premiering Sept. 13 on NBC, and it will be (no surprise) Phelps' acting debut, coming fresh off his record-shattering swimming feats in Beijing. It'll be Lil Wayne's first time on "SNL," too.

Phelps happens to be a fan of Lil Wayne, recently telling "The Today Show" that when he needs to rev up for cracking another world record in the pool, he cranks Wayne's "I'm Me."

The dynamic duo of Phelps & Wayne might also make another TV appearance together next month: Phelps reportedly will be introducing Wayne's performance at the MTV Video Music Awards.

(UPDATE: MTV confirmed it Thursday. Phelps will be a presenters at the VMAs.)