V8 star Greg Murphy waits on back problem

BACK DOWN: A back operation has put Greg Murphy in doubt for the Bathurst V8 endurance race.

Relevant offers

Four-times Bathurst winner Greg Murphy will give himself until the last minute before deciding whether to line up in this weekend's Phillip Island V8Supercar enduro.

Murphy is recovering from a back operation, which is hampering the way he brakes the car but says his fitness is improving rapidly.

He will drive the Castrol Edge Commodore in practice tomorrow and make a decision after that.

"I am definitely going to jump into the Commodore on Friday for some laps, but I can't guarantee I'll be racing," Murphy said.

"My back is heaps better but until I get into the car and do some laps I won't know if I will have repeatability of braking effort.

"My doctor said that I need to judge things myself based on the pain factor. The back's fixed, but the wound from surgery is still healing.

"At this stage I'd say it was 80-20 - that's not definite, but it's better than the 50-50 chance of a week ago."

If he decides against competing, he will be replaced by Daniel Gaunt, who completed almost 500km in the car at Queensland Raceway recently.

Whoever takes the seat will be teamed with rising young star Tim Blanchard, who is running second in the second tier Fujitsu series in just his first season in the competition.

The 23-year-old, who will make his V8 Supercar debut at Phillip Island, won the Australian Formula Ford Championship in 2007 before finishing runner-up in the British Formula Ford title.

Blanchard made his Fujitsu V8 Supercar Series debut in Adelaide earlier this year, finishing third overall.

- AAP