Sonny Bill Williams still has the fire to succeed in the NRL, according to Sydney Roosters coach Trent Robinson.

The 35-year-old and his family were released from quarantine on Thursday afternoon, hours before the Roosters take on Melbourne at the SCG.

“We’re doing good. We’re very happy,” Williams told the waiting media before heading off for a biosecurity check with his wife and four children.

“I’ll start training when we get the test back.”

After completing a medical examination, the dual international is expected to have his first training session with the NRL premiers at the weekend.

He has been using gym equipment while in quarantine and, although he’s had minor knee surgery, is expected to hit the ground running after his recent stint with Toronto in the Super League.

Williams last played in the NRL in 2014, in between stretches in rugby union where he earned 58 caps for the All Blacks and won a World Cup.

Despite his achievements, Robinson sensed Williams would rise to the challenge of playing in the NRL again and play a role in the Roosters’ charge to a third successive title.

“We can talk about all his attributes and people can see them, it’s the courage he has to play footy … that’s the biggest one,” Robinson said of Williams.

“Around all the talents you see, the man has got a fire in him, he’s got a hunger to perform and he loves playing in a team environment.”

Williams is pencilled in to make his return in their round 17 grand final rematch against the Raiders in Canberra on September 5.

Robinson played his cards close to his chest when asked about how he planned to use the veteran.

“I’d like to keep those private, the conversations between Sonny and I about the way we’ll use him,” Robinson said.

“We’ve had lots of discussions and then we’ll start to see him move and how he connects with the guys around him and that will give us a further idea about how we will use him.”