Brisbane caretaker coach Peter Gentle is fearing the worst for Kotoni Staggs, with the centre Bronco suffering a potential ACL injury in the Broncos' loss to the Cowboys on Thursday night.

Staggs, 21, has been outstanding in 2020 and was starting in the number six jersey for the first time this season, which has been the fifth starting five-eighth the club have had in the last seven rounds.

In theĀ 11th middle, the Staggs went down and was clutching his knee before having to be helped off the ground.

With initial thoughts of an ACL, Staggs could spend up to nine months on the sidelines.

"He is not good at all. He will go for scans but the initial thoughts are that it is an ACL, but we will wait to get confirmation on that," Gentle said.

"It is the number six jersey again and very early in the game. It has been one of those years.

"A lot of our attack happens around [Staggs] and I was really excited about him playing the role this week."

Despite the Broncos taking out the wooden spoon in 2020 and the first in the clubs history, retiring club legend Darius Boyd said the year wouldn't take away from what he has achieved in his 337 first grade game career.

"It is a funny game, rugby league. We have talked a lot about milestones this year at various stages but this year or this game doesn't change things for me," Boyd said.

"It is a great bunch of blokes. The staff have done a great job in a tough season, and Peter [Gentle] coming in late.

"We have to apologise to our fans and everyone that supports this club but it has been a challenging season for a number of reasons with injuries, COVID and coaching changes but there are no excuses.

"There is a quality group for the club to get behind and we have seen it with teams before where a team gets derailed for various reasons and it is very hard to come back from."