Mike Conway dropped out of this weekend's IndyCar season finale at Fontana on Thursday, saying he is not comfortable racing on oval tracks.
The British driver said he had asked A.J. Foyt Racing to sit out Saturday night's race at Auto Club Speedway. He will be replaced by Wade Cunningham.
Conway suffered serious leg and back injuries in a 2010 crash at Indianapolis, and wrecked there again in this year's race.
"I'm truly sorry for putting the team and our sponsors in a difficult position, but this is the hardest decision I have ever made in my racing career," Conway said in a statement. "I've come to realize I'm not comfortable on the ovals and no longer wish to compete on them. I want to stress that I am not finished racing and to this end, I would love to continue with Foyt Racing, but that's something we need to discuss in the future."
There has been a general uneasiness in IndyCar about racing on fast and high-banked ovals since Dan Wheldon's death in last October's finale at Las Vegas. Drivers fretted for months about the compatibility of the car on some of the ovals, and they took a hands-on approach to helping the series decide on the aerodynamic package used at Texas in June.
The Texas race was the first high-banked oval for IndyCar since Wheldon's death, and drivers were relieved when the approved configuration produced a safe and exciting race. It's helped alleviate the tension headed into Auto Club Speedway, which is a fast, wide oval.
Many teams participated in Wednesday's eight-hour test session at the track, and drivers seemed much more at ease in large part to a formula that uses less downforce and prohibits drivers from being wide-open all around the track. The setup makes the cars harder to drive, and puts the emphasis back on skill.
Conway has run 22 oval races in IndyCar. His best finish was an eighth at Iowa in 2009. He was 20th in points with three top 10 finishes in 14 races this year. He was a season-best third at Toronto, and was second in qualifying two weeks ago at Baltimore.
Team director Larry Foyt said the organization admired Conway's decision to come forward with his concerns.
"Mike's been a great asset to our team, and I'm disappointed that we can't finish out the season together," Larry Foyt said. "However, it took a lot of courage for Mike to come forward and we respect him highly for that and we certainly want to honor his decision."
Cunningham had planned to attend Saturday night's finale as a spectator. He ran the Indianapolis 500 this year for Foyt in a second entry that finished 31st with an electrical problem. It's the only race Cunningham ran this season.
He has made five previous IndyCar starts, all on ovals, and including last year's finale at Las Vegas.
Of Cunningham's eight Indy Lights victories, six were on ovals, and he won the 2005 race at Fontana in his championship season.
"Fortunately, Wade was available to drive for us, and we're looking forward to working with him again," Foyt said.