Broncos co-captain Brodie Croft claimed on Wednesday Turpin would be given "every chance" to prove his fitness for the Suncorp Stadium showdown.

But the lively rake is reportedly facing up to six weeks on the sidelines, opening the door for Paix to make his NRL debut.

In another blow to Brisbane's already depleted pack, it is believed Turpin has suffered a fracture below his knee and is expected to join captain Alex Glenn (leg laceration), David Fifita (knee) and Tevita Pangai (suspension) on the sidelines.

After playing his junior footy as a half, Paix is now tipped to step in and play up to 80 minutes at hooker after Brisbane released ex-Queensland rake McCullough to Newcastle last weekend.

McCullough will make his Knights debut in Sunday's clash with Canberra after losing his Broncos No.9 starting gig to Turpin and signing for Newcastle for the rest of 2020.

"If Paixy is to debut we have every confidence in him to do the job for the team," Croft said.

Paix is set to make his NRL debut along with teenager Tesi Niu, who has been named as a Broncos bench utility.

Niu may have never tasted NRL before but has already played Test football, impressing in Tonga's 14-6 upset over Great Britain last October.

Fellow co-captain Patrick Carrigan said the Broncos would be aiming to bounce back from last week's 34-6 loss to Parramatta and provide Paix a debut to remember.

"We have made it clear to each other that any time there is a debut or milestone game this year we want them to get them the win because you remember it for a long time," he said.

When he comes off the bench, Niu will feature in a new-look backline reshuffled after centre Kotoni Staggs copped a one week ban for a high shot on Eels pivot Dylan Brown.

Australian Associated Press