"He underwent surgery (Friday) morning. It went well. He is in ICU with a heart contusion," the Moores' spokeswoman, Chelsea Lawson, said Friday morning. "Doctors are optimistic."

Friday night, Lawson said Moore's mother was reporting "that he's improving by the minute." Caleb's brother Colten suffered a separated pelvis after a wreck on the same jump moments later. Colten was treated and released and by late Friday afternoon was back home in Krum, Texas recovering, Lawson said.

Moore and his brotherColten crashedon the same jump during Thursday night's snowmobile freestyle finals at the Buttermilk ski area.

Caleb came up short on a backflip Thursday, digging his sled's skis into the snow and slamming the landing. The 450-pound snowmobile bounced into his head as he tumbled. He was knocked out briefly, suffering a concussion.

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