Shaq immediately tries to sabotage Jimmy's team by inviting them to his Super Bowl party, and the guys play a crazy game of "What's Behind Me?"
Even more amazingly, Shaq didn't even seem to care which team he was going to back for this bet as he totally let Fallon call out his choice first. The native New Yorker surprised no one by going with the New England Patriots.
"Alright, I got the Rams," Shaq said quickly. "And if the Patriots win, I will take some superglue make it a chapstick and walk around with this thing on my lips for 20 minutes."
"This thing" is a fake life-sized fish-head necklace Shaq gave Jimmy as a goofy gift. When he challenged Jimmy to follow suit, Jimmy balked at the idea of using actual superglue for this one and we don't blame him. That stuff permanently bonds to human skin.
"I can't do superglue. I have really sensitive lips," he explained, to which Shaq challenged him to kiss him on the cheek and prove it. Of course, Fallon did so immediately and Shaq agreed here was no way he'd survive a superglue fish kiss.
The guys are clearly genuine friends as that warmth and affection came through in their every interaction. It was really sweet to watch, and their banter was so silly we caught ourselves smiling at just how much they were enjoying each other's company.
Later, however, Jimmy wasn't having nearly as much fun when they started talking about Shaq's epic pre-Super Bowl parties, which have become more like sports-themed music festivals with Shaq as the resident DJ introducing his famous friends from the industry.
And he had a special invite this year. Since Jimmy chose to back the Patriots, Shaq totally wanted to party with them. "Gronkowski, I need you at my party," Shaq said into the camera. "I got tickets, I got passes for your friends and family."
They showed a clip of Gronk legitimately jumping up onto Shaq's shoulders from the firs-ever Shaq party, and that's quite a physical feat considering how enormous Shaq is a 7'1".
Both Jimmy and Shaq agreed that Gronk was the life of the party and he definitely imbibed more than a little. "When you leave the party I want them to call you Drunkowski," Shaq said into the television, screen, but something tells us he wasn't tempting the Patriots' tight end one bit.
Jimmy was shouting at the television screen, too. "He does not have passes. Do not go," he pleaded with Gronkowski. "Sleep. Have the best night's sleep ever." By the end he was pleading with the Gronk to just go to sleep now to make sure he was well rested enough for the big game.
Elsewhere during the show, they played one of Fallon's silly games, but it actually included a genuine moment of friendship between them that touched Jimmy's heart.
But mostly it was two guys looking at ridiculous things one at a time and trying to get the other guy to guess what it was simply by describing it (minus a few key words).
We're not sure what was funnier, the various silly things they had to describe, or Shaq's response when Jimmy was trying to describe Shrek to him.
We thought Jimmy did pretty good by saying, "Mike Myers [was] the voice of this cartoon movie. He's a monster, he's green."
And from that, Shaq said, "Spongebob the Squarepants?"
Check out the whole game and find out how Shaq threw some pretty hilarious shade at Charles Barkley during the final round in he video above.
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