"These are gargantuan shots," Stewart laughed, as she struggled to slurp down the colorful shots.
"You don't have a premiere or anything tonight, do you?" Fallon joked.
As Fallon's announcer and right-hand man, Steve Higgins, called out foot and hand placements, it became increasingly apparent that the 26-year-old actress was a bit more nimble and limber than the 41-year-old host.
Finally, after Stewart strategically forced Fallon into a difficult pose, the final move pushed Fallon off balance and sent him sprawling to the floor. Stewart was her usual shy self as she bashfully basked in applause.