Denny Hamlin suffered spinal fracture in Fontana crash on Sunday

Denny Hamlin has been released from hospital after suffering a compression fracture in his lower spine at Fontana on Sunday.

Hamlin was involved in a last-lap crash with Joey Logano as the pair duelled for victory in the Auto Club 400 at the Californian venue.

Joe Gibbs Racing have, as yet, given no indication how long the championship challenger would be out for, although there is no NASCAR race scheduled until 7 April at Martinsville Speedway.

Hamlin walked out of the hospital under his own power, but a reporter from USA Today confirmed that he was wearing a back brace.

The crash, which was the second in successive weeks between the bickering drivers, happened at a part of the track that does not have energy-absorbing SAFER barriers.

Fontana spokesman David Talley said SAFER barriers are installed upon NASCAR's recommendation, and track officials will wait to see what, if anything, NASCAR recommends after Hamlin's accident.

"NASCAR is reviewing the incident and any improvements that can be made, will be made," Talley said.

"If NASCAR feels that additional SAFER Barriers are needed, then we will absolutely make those enhancements. SAFER barrier recommendations are based on past history and this is a situation we, nor NASCAR has ever seen at this track before."