NZ V8 champion Greg Murphy has received surgery for a back injury, putting him in doubt for October's Bathurst event
The four-time Bathurst 1000 champion is also almost certain to miss the next V8 meeting at Phillip Island in September.
The 38-year-old had surgery yesterday to fix a bulging disc after he collapsed at home complaining of serious back pain.
"I had a bulged disc in my lower back, the L5, which pushed the nerve off to the side and created a problem with my left leg," Murphy said after he was discharged from hospital.
"That caused a major strength loss in my left leg and I need that back as I left-foot brake, a key component of my driving.
"In one aspect, with three weeks until our next race the timing's good. Now the question is how long is the recovery process?"
Murphy has had a difficult V8 season, sitting at 25th, but remains positive he would be fit enough to compete.
Castrol Racing team owner Paul Morris said a search for a driver to potentially take Murphy's place alongside rookie Tim Blanchard for Phillip Island was underway.
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