King's Lynn Stars and Berwick Bandits rider Kozza Smith has been ruled out for up to six months after breaking his leg at the Australian Championship.
The 27-year-old missed the back end of last season when he dislocated a shoulder in the Elite League play-offs.
"It's a devastating blow for him and he's going to be out for a little while," Stars boss Rob Lyon told BBC Radio Norfolk.
"This particular injury to the femur is probably the worse he's had.
He added: "It's going to be realistically at the very best between four and six months."
"Knowing Kozza he'll be out for the minimum time possible. He's already up on his feet after the operation.
Smith was poised to double-up for the Stars and Bandits and is likely to miss up to the first four months of the 2012 campaign, which begins in March.
"We have to sit down and look at the options," said Lyon. "There's no need to panic and make a decision straight away."