Toyota's Ralf Schumacher must wait until Saturday for clearance to race in the U.S. Grand Prix after suffering a repeat of his crash last year at Indianapolis.
"Thankfully, I am feeling okay," said the German after precautionary checks in hospital. "But that was quite a big accident.
"Lightning is supposed not to strike twice in the same place but on this occasion I guess that does not apply to me."
A team spokeswoman said the 29-year-old, who had a brain scan after complaining of blurred vision, would have to pass a medical at the circuit on Saturday morning before being allowed back in the car for final practice and qualifying.
Toyota's reserve driver is Brazilian Ricardo Zonta.
Ralf, who missed six races with Williams last year after suffering the worst accident of his Formula One career, smashed into the wall at almost the same spot on the last banked corner where cars reach speeds of about 300 kph.
Fortunately, safety improvements since last year meant he hit an energy-absorbing SAFER barrier that has been extended 70 metres along the pit straight.
This time he walked away from the wreckage, with practice halted, rather than lying slumped in the car as rivals threaded their way through the wreckage in last year's race.
"I was approaching the last corner when I felt something go wrong on the left-hand side. We will now have to investigate exactly what happened and why," he said.
"I've never had much luck here as a driver but I'm still hopeful that record will improve."
NO FEARS
Ralf had said earlier that he had no fears about returning to the scene of last year's crash.
"If I were afraid of being in a Formula One car I'd stay at home," he said.
"I remember nothing basically. I just remember the start and then when I woke up in the hospital more or less. That's it," he said of last year's crash.
The younger brother of Ferrari's seven times world champion Michael was later found to have suffered two hairline fractures of the spine.
Like last year, Friday's accident was also caused by a sudden tyre deflation with Zonta suffering a similar problem at a different and less dramatic point of the circuit.
"Maybe there is a point on the track where we are running over and cutting our tyres because it seems to occur on the outside tyre," said chief engineer Dieter Gass.
"We made sure that we had no problem on the car and that the suspension was okay."
Ralf is eighth in the championship with 20 points, seven adrift of Italian team mate Jarno Trulli who has enjoyed three podium placings for a team that had not finished in the top three before this season.
He said earlier that a strong points finish, and possibly a podium, was the target for the weekend.
Toyota are fourth in the constructors' standings, level on points with third placed Williams.