Phoenix police say 23-year-old Nathan DeWitt, originally from Mount Vernon, Wash., died early Wednesday after being taken to a hospital.
Police and Phoenix Fire Department crews responded to a rollover crash shortly after midnight and found an SUV on its side.
They say DeWitt crawled out of the vehicle and had been shot.
Police say it's still unclear if DeWitt died from the shooting wound, injuries from the crash or both.
Detectives say DeWitt possibly was at Christmas party before the shooting.
The Arizona Republic reported Thursday that DeWitt was the 2005 Pacific Northwest yo-yo champion and placed eighth in the 2008 competition and 18th last year.