Gordon was among participants in a desert ride in high-powered vehicles on Jan. 31 in which Stewart crashed. Because of his injury, Stewart will not drive in the upcoming Daytona 500 and likely miss a large chunk of Sprint Cup’s early season.

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Details are beginning to emerge on the accident in which Stewart was left with a burst fracture of the L1 vertebra. He had surgery on Wednesday, and there was no immediate indication on how long he would be out of action.

Stewart has never won the Daytona 500, and Feb. 21’s race would have been his last shot. Stewart, a three-time Cup champion, will retire after the 2016 season.

Gordon, a four-time Cup champion, retired after the 2015 season. He told Fox Sports of his involvement in Jan. 31’s dune car excursion in the desert near San Diego. Also involved were Sprint Cup driver Greg Biffle and Hendrick Motorsports’ Ray Evernham, and drag racing legend Don Prudhomme.

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Tony Stewart (Getty Images)

Stewart’s vehicle apparently landed nose first after jumping a dune, reports said. The accident came while Stewart was at the back of a line of ATVs, and as a result he was left behind.

Once Stewart’s absence was noticed, Gordon said, he and other participants circled back to find Stewart.

Gordon’s description:

Stewart was airlifted to a hospital where, according to reports, he told an ER physician:

Stewart-Haas Racing, the team Stewart co-owns, announced Thursday that it would find a replacement driver. NASCAR teams are gearing up for Speedweeks activities at Daytona International Speedway, the famed Florida facility where the first stock car races of 2016 will be held.

Stewart’s injury and surgery indicate it could be months before he resumes racing.