Top Gear's James May says he is convinced his fellow presenter Richard Hammond is "perfectly intact" after a conversation at his hospital bedside.
Richard Hammond has been moved out of intensive care
Mr Hammond suffered a "significant brain injury" when he crashed a jet-powered car at a speed of up to 300mph during filming near York.
Mr May said it was not a long talk "but it was a conversation".
"I'm not a doctor but I am his mate and I believe that deep inside the Hammond I know is perfectly intact," he said.
The accident is being investigated by the BBC, the police and the Health and Safety Executive.
Mr Hammond, 36, was earlier moved out of intensive care at Leeds General Infirmary, where he has been since Wednesday, and doctors said he is making "satisfactory progress"
Doctors said his condition had changed from "serious but stable" to "stable".
The doctors treating him have previously said they are "reasonably optimistic" he will make a good recovery.
Mr Hammond's wife, Mindy, and Top Gear's other host, Jeremy Clarkson, have also been at his bedside.
Mr Clarkson told the Sun newspaper that he had insulted Mr Hammond's driving skills - prompting a smile from Mr Hammond.
He also said Mr Hammond had no visible injuries following the ordeal he had been through other than a black eye.
The presenter had been driving a jet-powered dragster similar to the Vampire - used by Colin Fallows to set the British land speed record of 300.3mph.
Mr Hammond had to be cut free from the car after eyewitnesses at the Elvington airfield near York described how he "veered off to the right" and the car's parachutes opened.
Primetime Land Speed Engineering, which is jointly run by Mr Fallows, supplied the car and a support team for the event.
A spokesman for the firm said the vehicle Mr Hammond was driving "had been prepared and was being operated to the highest of standards".
The BBC said in a statement that it had started an investigation into the accident and promised full co-operation with the HSE.
"We continue to be concerned about [Mr Hammond's] condition and we are keeping in touch with his family," the statement said.
Top Gear has courted controversy in the past over its big-budget car stunts, and in 1999 a group of MPs criticised the series for being "obsessed with acceleration and speed".