The retired NBA player, 45, showed he still has that competitive spirit as he went head to head with the Saturday Night Live alum, who is broadcasting this week from Orlando.
Fallon, 42, got the audience on their feet with House of Pain's 1992 hit "Jump Around," but Shaq kicked things up a notch with Bobby Brown's "My Prerogative." First he brought an audience member on stage and then was joined on the 1988 hit by Mr. Worldwide, Pitbull, who was the night's musical guest.
"That's not fair!" Fallon exclaimed. "I'm gonna up my game."
The talk show host then slipped behind a screen to prep for his next number, "Beauty and the Beast," and came out dressed as Ariana Grande, who recorded a new version of the song with John Legend for the recently released live-action film.
Fallon began the song with his left side facing the camera as he performed the "Dangerous Woman" singer's part of the song and then turned the other cheek to reveal the more masculine right side of his wardrobe.
For the final song, Shaq insisted that they duet on Elton John and Kiki Dee's 1976 hit "Don't Go Breaking My Heart."
Watch the video above to see the Olympic gold medalist massage Fallon's shoulders before leaning in for a kiss, spanking the comedian on the butt and then picking him up and rocking him like a baby.
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