Caleb Moore, an award-winning 25-year-old snowmobiler, died Thursday following complications of an injury he suffered on Jan. 24 at the freestyle final of the Winter X Games in Aspen, Colorado. Moore was knocked unconscious after a failed backflip, a move ESPN claims he had "landed several times previously." Initially diagnosed with a concussion, the discovery of bleeding in Moore's heart prompted doctors to perform emergency surgery. On Sunday, a spokesperson for the family announced that he had suffered a "brain complication." Moore's death is the first to occur at the Winter X Games in 17 years. He leaves behind a younger brother, Colten, who competed alongside him last Thursday.