Updated

Driver Denny Hamlin is expected to miss the next six weeks of races after he sustained a compression fracture in his lower back during an accident last Sunday at Auto Club Speedway.

According to a release from Joe Gibbs Racing, Hamlin was evaluated by Dr. Jerry Petty of Carolina Neurosurgery and Spine Associates in North Carolina on Tuesday after suffering an L1 compression fracture.

"Dr. Petty determined that Hamlin will not require surgery but will need time to properly heal, which is estimated around six weeks time," JGR said in its release. "Dr. Petty will make the determination when Hamlin will be able to return to racing this season.

JGR also noted that no decision has been made on a replacement driver for Hamlin during his absence from the NASCAR Sprint Cup Series.

"I wish I got good news today.. I didn't," Hamlin posted on his Twitter account.

The series is off this weekend for Easter before heading to Martinsville Speedway, a half-mile racetrack, the first weekend in April.

"If me getting back in a car was based on pain tolerance then I would be in the car next week. There's just more to it that I can't control."

Texas (April 13), Kansas (April 21), Richmond (April 27) and Talladega (May 5) are those races that follow the April 7 event at Martinsville.

Hamlin's crash at Fontana, Calif. occurred on the final lap when he was battling his former JGR teammate, Joey Logano, for the lead. Both drivers made contact and spun. Hamlin skidded down the track and then slammed hard into the inside retaining wall. His car came up off of the ground and spun around after it ricocheted off of the wall.

Hamlin climbed out of his car under his own power but then laid down on the track, as safety personnel quickly tended to him. Shortly after, he was airlifted to nearby Loma Linda University Medical Center. Hamlin remained hospitalized until late Monday. He was wearing a back brace when he left the hospital.

Driving the No. 11 car for JGR, Hamlin made the Chase for the Sprint Cup championship for the seventh consecutive year in 2012, every year he has been a full-time competitor in the series. He won rookie-of-the-year honors in the series in 2006. Hamlin also has 264 consecutive Sprint Cup starts. He is currently 10th in the point standings.