Brisbane aren't deluding themselves when it comes to finding a replacement for hooker Andrew McCullough, out for the season with a knee injury just as the NRL stakes begin to head north.

"You can't," was the answer from Broncos forward Korbin Sims as McCullough stood nearby talking to his replacement for the rest of the campaign, regular halfback Ben Hunt.

A loss to Parramatta was disappointing enough for the Broncos before the verdict came in on McCullough, who has been one of their best players all season and a key contributor to their standing on the ladder (fourth on 28 points).

His work around dummy-half has been exceptional and he brings almost 45 tackles a match, which is the area Brisbane will struggle to replicate. Hunt has the edge as a ball-player but won't be likely to adjust to that sort of defensive intensity in a hurry.