They were racing side-by-side on the last lap for the win when they banged into each other. Both cars spun and Hamlin's hit head-on into an inside wall not protected with energy-absorbing SAFER barriers.
He spent Sunday night in a Southern California hospital, where he was diagnosed with an L1 compression fracture in his lower back. He saw Dr. Jerry Petty of Carolina Neurosurgery and Spine Associates on Tuesday, and Petty determined the driver will not need surgery but needed a minimum of six weeks to heal.
NASCAR is off this weekend, so Hamlin could miss only five races if the healing process meets Petty's estimate. But the next five weeks include stops at Martinsville Speedway and Richmond International Raceway, where the Virginia-raised driver has a combined six Sprint Cup victories.
Hamlin also races in his annual charity event at RIR, and will now have to sit that out, too.
Darby did not think Logano intentionally wrecked Hamlin.
"It was the last lap of the race, and the last time they were both going to see turns three and four. They were side-by-side. If somebody was of the mindset to retaliate, they probably would have been lined up nose-to-tail and somebody would have drove into the other car and spun him around," Darby said. "In this case, that is so far from the opposite, that it never even crossed anybody's mind that I'm aware of that paid attention to the race."
Meanwhile, NASCAR is still going over data from Hamlin's accident and will need to meet with officials from the University of Nebraska, home to the engineering school's Midwest Roadside Safety experts, and IndyCar before making any recommendations on whether a SAFER barrier should be installed where Hamlin hit.
When NASCAR first began installing SAFER barriers following the 2001 death of Dale Earnhardt, the priority were locations where cars frequently hit the wall. Officials at Nebraska also make recommendations not to install the barriers at certain points at a facility because of various issues, including the potential for a car to sling-shot back into traffic after impact.
Track officials usually follow the recommendations.
Tom Gideon, senior director of safety research and development at NASCAR, said where Hamlin hit was not an area that cars frequently make impact.
"Each point on the track we look at the application and you don't want to put (barriers) in places where the angle of impact may not be appropriate for a SAFER barrier," Gideon said. "We also look at the possibility of impact and the frequency of impact, and when you look at the frequency of impact, especially at oval tracks, it's reasonable to think they are going to be with outside walls."
NASCAR doesn't race at Auto Club Speedway again this season, but IndyCar's October finale is scheduled at the track. IndyCar officials said the series is working with NASCAR, Nebraska and the Fontana track officials to study the accident and see if "any changes need be addressed prior to our race at Fontana."
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