Vaught said Moore's only previous injury was a bruised hip that sent him to the hospital last year, where he was treated and released.
"In sports, everybody makes mistakes, even if it's rare. Caleb made a mistake. That's it," said Vaught, who witnessed Moore's crash.
The spills at Winter X weren't just limited to snowmobiles. Rose Battersby suffered a lumbar spine fracture in a wipeout on a practice run before the skiing slopestyle competition. She was transported to Denver on Sunday and had feeling in all extremities, according to X Games officials.
Soon after her crash, Ashley Battersby, who's not related to Rose, wiped out on the course and slid into the fencing. Battersby was down for at least 30 minutes before being carted off on a sled and taken to a local hospital with a knee injury.
There also was a bad wipeout in the snowboard big air competition, when Halldor Helgason of Iceland suffered a concussion when he over-rotated on a flip. He raised his hand to salute the crowd as he was being taken off the icy course.
Moore's crash came just over a year after one of the most high-profile deaths in the extreme sports community.
Canadian freestyle icon Sarah Burke died Jan. 19, 2012, after sustaining irreversible brain damage in a training accident in Park City, Utah. The 29-year-old was a pioneer in the sport and a driving force behind the inclusion of slopestyle and halfpipe skiing at next year's Winter Games in Sochi.
AP Sports Writer Pat Graham contributed to this report.
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