Brad Paisley goofed off for a good cause during comedian Will Ferrell's Best Night of Your Life -- a benefit to support cancer survivors -- on Friday evening (Oct. 6) at the Greek Theater in Los Angeles. Joined onstage by Chad Smith of the Red Hot Chili Peppers, Duff McKagan of Guns N' Roses and Ferrell himself, dressed as Paisley's disheveled, shirtless older brother, "Gary," the country superstar performed a fast-paced rendition of Van Halen's "Hot for Teacher." Readers can press play above to see a clip of the show.

As evidenced by his smokin'-hot guitar solo, Paisley brought the musical talent to his comedic duo with his long-lost "brother," but what Farrell lacked in vocal skill, he made up for in sheer enthusiasm.

Prior to the performance, Ferrell took the stage as Gary, complete with sunglasses, a wig, and a drink in hand. "I'm his older brother, Gary Paisley," Ferrell told the crowd. "Thanks, Brad, for not leaving me a ticket tonight, but I got in anyway. Despite our estrangement, I'm really proud of him. He never lets me sing a song, but whatever," the disgruntled Gary continued.

In addition to the brothers' set, the evening featured performances from members of Pearl Jam, Dave Matthews Band and Coldplay, as well as appearances from a host of comedians, including Jerry Seinfeld, Jimmy Kimmel, Samantha Bee, James Cordon and Conan O'Brien. The event was held to benefit Cancer for College, an organization which provides college scholarships to cancer survivors across the United States.

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