Denny Hamlin will be sidelined at "around six weeks" because of a fractured vertebra sustained in a last-lap crash at California.
Hamlin was evaluated Tuesday by Dr. Jerry Petty of Carolina Neurosurgery and Spine Associates. While it was determined Hamlin won't need surgery, the L1 compression fracture in his lower back needs time to heal.
''Dr. Petty will make the determination when Hamlin will be able to return to racing this season,'' Joe Gibbs Racing said in a statement.
While there was no official word from Hamlin in the statement, he tweeted: ''I wish I got good news today.. I didn't.''
Hamlin has made 264 consecutive Sprint Cup Series starts, 13th most among active drivers. He raced two weeks after undergoing knee surgery during an off week in 2010, and completed the race at Phoenix without a replacement driver despite obvious pain.
If he heals according to Petty's estimated timeline, he'd only miss five races because NASCAR is off this weekend. But among the next five are stops at Martinsville and Richmond, where the Virginia-raised driver has a combined six wins. He also hosts and competes in an annual charity race at RIR.
Joe Gibbs Racing said no decision has been made on a replacement for Hamlin, who is 10th in the Sprint Cup Series standings. But the team has former Cup regulars Elliott Sadler and Brian Vickers in its stable in the Nationwide Series, and both will likely get seat time in the No. 11 Toyota.
Vickers is scheduled to drive the Sprint Cup race at Martinsville for Michael Waltrip Racing.
Hamlin was injured when his car hit head-on into an interior wall at Auto Club Speedway after contact with Joey Logano.
Hamlin and Logano have been feuding over the last month, and neither wanted to give an inch as they raced side-by-side on the last lap for the win. Both cars ended up wrecking after the contact.
NASCAR ruled that neither driver was trying to intentionally wreck the other during the battle, and no penalties were issued Tuesday. NASCAR chairman Brian France said earlier Tuesday that while Hamlin's injury was unfortunate, the battle for the win was the kind of throwback racing he expects out of the drivers.
''I have said repeatedly, every minute, that contact, especially late in the race when you are going for a win, that's not only going to happen - that's expected,'' France said in a telephone interview with The Associated Press. ''Both of them did exactly what I think you would do when you really, really want to win. Getting some contact, trying to race extra hard to win the race, that's what we're about.''
Dale Earnhardt Jr. is the last championship-level driver to sit out, missing two races last season in the middle of the Chase for the Sprint Cup because of concussions. Vickers missed more than half of the 2010 season because of blood clots.
Sterling Marlin, who led the points for 25 weeks in 2002, missed the final seven races of the season with a fractured vertebra in his neck.
The time out of the car could cost Hamlin a spot in the 12-driver Chase field. He has made the Chase every year since entering the Cup Series in 2006.
Although he's 10th in points, he'll fall after missing Martinsville. The top 10 in standings after the 26th race earn a spot in the Chase, and the two winningest drivers not already eligible get the final two berths.
Hamlin does not have a win this season.
