Gavet has been binned twice in Newcastle's past three games after a much-publicised refereeing crackdown.

His 10 minutes in purgatory against Brisbane in round 15 put Newcastle under enormous pressure before they steadied to score a 26-12 victory.

Then last week, the 12-man Knights leaked two tries in his absence during their costly 20-14 loss to lowly Canterbury.

There was speculation Knights coach Nathan Brown would drop Gavet to NSW Cup as punishment for his indiscretions, but he has instead shown faith in the 29-year-old Samoan international.

Gavet intends to repay Brown's trust with a big game against a star-studded Sydney Roosters team, led by long-time rival Jared Waerea-Hargreaves, at the SCG on Saturday.

"I've complete confidence in Browny, and he ended up picking me this week, so I really want to make sure that I stay squeaky clean and I'm able to do the best I can for the boys," Gavet said.

Gavet said there had been "a change-up" in recent weeks in the way referees were handling off-the-ball incidents, such as his hit on Canterbury's Chris Smith last week.

"There is a fine line with what I'm supposed to bring to the team, with the aggression ... five or six weeks ago, most were let go," he said.

"Or at most a penalty. But I've still got to be at fault.

"It was something that I had been used to doing, but it ended up coming back to haunt me."

He said it was chastening to think that his sin-binning on Friday was a major turning point in the game.

The Bulldogs piled on 14 points while he was cooling his heels, to grab a matchwinning lead.

"For us to end up losing, you can't help but feel you were responsible for part of that," he said.

"To see how beat up and broken they were, not only physically but mentally, it's hard for anyone to see that.

"All the more reason for me to hit the ground running this week and make sure I don't let them down."

Gavet said he had been playing against Waerea-Hargraves for the best part of a decade and always enjoyed the challenge.

"Jared hasn't changed since I played him in the 20s," Gavet said.

"We're the same age, and he brings a similar style of footy that I normally play.

"It's funny, because we're actually really good mates off the field, but you've really got to give it to him on the field. If not, then they end up steamrolling most teams ... you can only match their fire with fire.

"And it's not solely me. Our whole forward pack have to play really aggressive."

Knights utility Jamie Buhrer said coach Brown has stressed the need for improved discipline against the Roosters, having lost seven players to the sin-bin in their past seven games, and having conceded more penalties this season than any team except Penrith.

"We're well aware of our need to improve in that area," Buhrer said.

"It's something that Browny has been speaking about for a number of weeks.

"It's not something he's just dropped in our lap, so to speak. It certainly affected us on the weekend and something we need to rectify."

Waerea-Hargreaves is free to take his place on Saturday after beating a dangerous-contact charge at the NRL judiciary on Tuesday night.

The Kiwi prop was facing a two-game ban for his grade-one charge after clashing heads with North Queensland's Josh McGuire last Sunday.

But the three-member panel of Tony Puletua, Bob Lindner and Sean Garlick took just 10 minutes to find Waerea-Hargreaves not guilty.