The gymnast – who recently returned from a record-breaking run at the Rio Olympics – had Tatum totally starstruck.
“I’m gonna freak out,” the 36-year-old gushed to DeGeneres, promising, “I’m gonna freak out more [than her], I bet.”
The actor said he and wife Jenna Dewan Tatum watched all of Biles’ Olympic competitions, praising the teen gymnast as “the greatest of all time.”
“I have a theory though, my theory is that she’s so tiny, she has a harder time holding on to the ground than just going up,” Tatum revealed. “I think she’s got really strong toes and that helps her hold on to the ground … to keep herself from flying away.”
Later, the actor – who was there to promote Magic Mike Live – posed as a medal holder for Biles, who was surprised to see the actor with her hardware draped across his arms.
The pair hugged and posed for a selfie, with Tatum asking, “Do I just follow you around now?”
Tatum’s live Las Vegas Magic Mike show also made its debut during the episode, starting off with a one-on-one lap dance for one of DeGeneres’ audience members.
The entire crew of hunks then took the stage to perform a routine to “Pony,” ripping off their shirts while they did flips in front of the cheering audience.
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Of the show, which will kick off at the Hard Rock Hotel & Casino in March 2017, Tatum told DeGeneres, “We just thought let’s go make something cool. Let’s go make something really for you ladies and hopefully we’re going to be able to do that.”