Matt Gillett could prove the x-factor for Brisbane in Friday night's NRL preliminary final against Manly, warns Broncos assistant coach Allan Langer.

Young utility Gillett has been thrust into the five eighth role for the high stakes clash at the SFS following skipper Darren Lockyer's withdrawal because of his fractured cheekbone.

Langer said on Friday that Gillett would bring both a strong running and defensive game to the position and could just be the secret weapon the Broncos need to secure a ninth straight win and a grand final berth.

"He could be the x-factor tonight," said Langer from the team camp at Bondi.

"He probably wont play exactly the same way Locky was."

Langer said the Broncos would miss Lockyer's kicking game but had focused on that in training throughout the week.

"Matt Gillett can kick," Langer said.

"Andrew McCullough and Peter Wallace (also), they'll just add a bit more to their kicking game."

The match also sees the return of star back-rower Sam Thaiday to the Broncos after a two-week suspension.

"I think that two weeks off would have been great for him," Langer said.

"He's refreshed, he probably had a few niggling injuries that he's over.

"He's champing at the bit to be out on the field."

Langer said Manly, who had the week off with a bye, had a tough, physical pack and the Broncos were also wary of the young Manly halves Daly Cherry-Evans and Kieran Foran.

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