LOL! Jennifer Aniston Jokingly Smashes Jimmy Kimmel's Desk, Cuts His Hair

Jennifer Aniston lent her comedic firepower to Jimmy Kimmel's show on his first night competing head-to-head with Jay Leno and David Letterman at 11:35 EST, as the actress did a number of entertaining bits to usher in the new era of the ABC late night franchise on Tuesday.

The Friends star wasted little time, smashing Kimmel's desk with a sledgehammer and announcing, "That's out with the old, in with the new, we're going to 11:30!"

After Jimmy informed her she had mauled his new 11:30 digs, she joked the desk she'd just demolished was "not very well-made."

Later, the two discussed a vacation they had taken to Cabo San Lucas, Mexico with Jen's fiance Justin Theroux, Jimmy's fiancee Molly McNearney, and star pals John Krasinski and Emily Blunt.

"I've known your fiancé, Justin, for a while," Kimmel said. "Now, if I was you, I would eliminate all his friends right off the bat. I would not allow his friends to go on vacation with me. But you were very gracious."

Jen said Jimmy was a great vacation mate, as he and Justin prepared the group a large Italian dinner on New Year's Day.

"All of you boys were secure enough in your masculinity to join the women on spa day," she said, providing pictures of the outing. "So the girls had massages, whilst the men were having manicures and pedicures."

Watch the video on RadarOnline.com

For a last bit, Aniston, who has experience as hairstylist, gave Jimmy a snazzy trim to have him looking sharp for the task ahead.