Conan O'Brien mocked Jay Leno's Feb. 6 exit from The Tonight Show with one "good" joke on his late show, Conan. Credit: Jerod Harris/; Kevin Winter/Tonight Show/Getty Images

Make it count! Conan O'Brien probably has a lot of jokes he could make about Jay Leno leaving NBC's The Tonight Show, but he only needed one. The 50-year-old comedian mocked Leno's last night as host in the opening monologue of his late night show, Conan, on Thursday, Feb. 6.

"The Olympics start airing tonight on NBC. It's very cool. That's right, NBC has the Olympics," O'Brien said. "It's a big deal. NBC will finally get to show somebody who is OK with passing the torch."

After the audience cheered for the Leno joke, O'Brien gave a big thumbs up to the camera and started laughing. "I allowed myself one," he explained. "But it was a good one."

O'Brien was first to replace Leno on The Tonight Show back in 2009. He was forced out, however, less than a year later so Leno could take the job back.

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After 22 years behind the desk, Leno, 63, made his last appearance on The Tonight Show on Feb. 6, before Jimmy Fallon takes over as host of the show on Feb. 17. The emotional goodbye episode featured a star-studded Sound of Music parody with Billy Crystal, Kim Kardashian, Oprah Winfrey and other celebs singing "So Long, Farewell."