Both were casualties as the Blues put in their most impressive display of the season with their 40-12 win over Young at Twickenham on Sunday.

Dean Bristow has been cleared of any neck or back fractures after getting caught awkwardly in a tackle.

However the 31-year-old won't line up against Southcity at Harris Park on Sunday.

"It's some sort of upper back issue," Bristow said.

"I've had X-rays and have been cleared of any breaks but whether it is ligaments or a disc injury I don't know.

"It's a bit of a wait and see game. I'm in quite a bit of pain at the moment and just have to wait until that subsides.

"They didn't really give me a time frame on it and I'll need further scans to see if there is any further damage but they said it would be a pain related thing."

Younger brother Lachlan injured his ankle after dominating the early stages.

He too has been cleared of any breaks but is also set to miss the clash with the Bulls.

With the bye to follow, both Bristows are hoping to limit their time off the field.

"With the bye the week after it gives us three weeks to hopefully get right," Dean said.

"It is a fair bit of time but more than likely we will have to miss this week and see how things progress."

It will cause a major reshuffle of their spine to take on the Bulls for the first time since their 28-4 grand final win.

Jacob Toppin is expected to move into hooker but who comes into five-eighth is uncertain.

However the Blues will welcome back Jed Pearce and Tevita Aroha-Tuinauvai as they look to extend their unbeaten start to the season up against a Bulls outfit that is yet to score a win.

Bristow was impressed with how the team responded to the losses, which were further amplified when Toppin was sin binned.

"We will have to have a rejig and put some new blokes in there," he said.

"We got thrown into a bit of disarray with the new shape and structure we've set up this year but I'm confident the boys we throw in there will do a job.

"I think the blokes who jumped in there with little to no preparation did a great job."

It may have been messy but Bristow thought it showed the attitude which has helped turn the club around their fortunes after some tough times.

"It just typifies what we are about," he said.

"Everyone just rolled their sleeves up and did what we had to do to hang onto the win and even scored a couple of tries."

Southcity have an injury concern of their own with Mitch Curran injuring his ankle in the loss to Kangaroos on Saturday.

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