Knights winger Cooper Vuna admitted after the loss to St George Illawarra that he "got a bit emotional" before and after his EnergyAustralia Stadium farewell.

The Tongan international will join new rugby union franchise Melbourne Rebels at season's end.

But he left Knights fans with fond memories by scoring two tries against the Dragons, giving him 35 in 53 games for the club, including 16 in 16 games this year.

"A few tears started coming out before the game," Vuna said. "I was thinking this is the last time I'm ever going to be in this dressing room.

"It's a great club and a great bunch of boys.

"But I guess this is another chapter in my life."

Asked how he would like Knights fans to remember him, Vuna replied, "Just as someone who helped make people smile.

"I'm just a happy person and I like to get the crowd involved."

Knights coach Rick Stone said Vuna was "a little bit loose" when he first arrived in Newcastle in 2007 as a teenager but he quickly became a popular clubman.

"'It's a sad day for Coops," Stone said. "His attachment to this place is a lot stronger than people understand."