Caleb Moore, a professional snowmobile rider is in critical condition after a nasty crash during the Winter X Games in Aspen.

According to The Denver Post, the outlook is not good for the 25-year-old who crashed during a snowmobile freestyle contest on Thursday. He wasn't able to complete a back flip and the skis of the snowmobile dug into the snow. The 450-pound snowmobile slammed into Moore as he tumbled down the landing ramp. He was knocked unconscious but he later came to and didn't know what happened.

Moore was taken to Aspen Valley Hospital for a concussion, but doctors found bleeding around his heart. He was then rushed to Grand Junction's St. Mary's Hospital where he received emergency heart surgery. He is now in intensive care and remains in critical condition. He may also have brain complications.

Moore's family feels that Moore will not survive at this point, but they thanked his fans for the support and asked for prayers.

 "It's almost certain he's not going to make it," Caleb's grandfather, Charles Moore, told The Denver Post.

"Caleb is in critical condition and is being closely monitored," family spokeswoman Chelsea Lawson said according to the Post.  "The Moores want to express their gratitude to all of Caleb's fans, friends and family for their strong support and ask for continued prayers in the coming days. The family will not be making any other public statements for the time being. Thank you for respecting the family's privacy during this difficult time."

 Before his crash, Moore told The Denver Post that his career at the X Games started only 30 a month after he started practicing.

"Took a bronze medal after 30 days of practice," Caleb said. "It's been history from there. It's been a great ride."

 Moore won a freestyle bronze medal in his first X Games 2010. He won another bronze in 2011. In 2012 he won best trick silver, finishing behind  his brother, Colten, who won gold.

If Moore doesn't survive, it will be the first fatality of the 17-year-old Winter X Games.