12/23/2010 09:45 am ET | Updated May 25, 2011

Conan & Jack Black Guitar-Off: Host Curses On Air Before Epic Guitar Battle (VIDEO)

Wednesday night's "Conan" saw some serious action when guest Jack Black got his 15 minutes.

Black, who's been making the late night rounds promoting his new "Gulliver's Travels" movie, spent the first portion of the interview talking about his adorable parenting skills and new-found appreciation for bluegrass. But things ended quite differently after Black and Conan O'Brien challenged each other to a guitar-off to see who really rocks the hardest.

Things get tense at about 7:00 in when Black questions Conan, who spent the summer on tour with his band across the U.S., on his rock-ability. After Black refers to his guitar playing as a hobby, Conan responds that he knows his band could rock harder than Black's band Tenacious D. As Black cannot believe what was just said, Conan says uncensored:

"Did bullsh*t just crawl out of your ears?"

Conan's expletive got a riotous roar from the audience and most likely the people at home who aren't yet used to hearing Conan on cable after 10:00 p.m. Black was also pretty affected, and things almost got physical before Andy Richter suggested a guitar battle.

Check out the clip below to see the battle and a surprise twist at the end. You have to see what ensues when these two rock-loving funny men decide to face off.