Take that, Phelps! Olivia Munn enlisted champion USA gymnasts Aly Raisman and Simone Biles to help her against Michael Phelps during Lip Sync Battle on Sunday, September 11.

The 23-time gold medalist, 31, was shocked to see the fellow Olympians take the stage during the special live edition of the Spike TV series. Clad in tutus, Raisman, 22, and Biles, 19, danced around Munn, 36, as the actress performed Sia’s number-one hit, “Cheap Thrills.”

“When I found out that Michael Phelps was joining our set, I said the only way to beat a gold medal champion is to bring two gold medal champions,” the X-Men: Apocalypse star told host LL Cool J afterward.

Phelps was impressed with the surprise. “That was awesome,” he said. “I loved being on the team with these girls and seeing them perform is so special.”

The retired pro swimmer didn’t just sit back and cheer, though. During his set, he rapped to Eminem’s 2002 iconic, Oscar-winning anthem “Lose Yourself.”

We're patiently waiting to watch daddy @m_phelps00 on @spikelsb LIVE right now!! #lsblive

A photo posted by Nicole Michele Johnson (@nicole.m.johnson) on

Phelps’ performance earned him bragging rights. “Pretty salty we didn’t win. @oliviamunn @Simone_Biles @MichaelPhelps,” Raisman tweeted following the show.

Biles added, “lip sync battle @SpikeLSB thanks for having us & big thanks @oliviamunn we love u nice to meet you @llcoolj.”

Phelps had two special people rooting him — his fiancé, Nicole Johnson, and the couple’s 4-month-old son, Boomer. Johnson posted an Instagram photo of herself and Boomer getting ready to watch the episode on Sunday.

Watch the Lip Sync Battle performances in the videos above!

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