The two stars donned their tightest white pants, colorful sweaters and bowl-cut wigs Monday night to sing the recurring song together before Fallon, dressed in similar garb, came to contest the tightness of their pants.
"You say people are talking about your tight pants down at the penny arcade?" Ferrell said to Fallon. "I find that hard to believe because ever since we moved to this town, everyone we know has been talking about our tight pants."
After a back-and-forth between the Ferrell-Aguilera duo and Fallon, "The Tonight Show" host's character surrendered his spot as the one with the tightest pants.
In celebration, Aguilera's character belted the first few words of "Circle of Life" from "The Lion King."
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