Daniel Tupou scored his 100th NRL try as Sydney Roosters ended Newcastle Knights' top-four hopes with a 42-12 victory at the SCG on Saturday.

Roosters wing Tupou's second of the game early in the second half saw him hit the milestone in his 171st appearance, helping his team move ahead of Parramatta Eels on points difference and into third.

Josh Morris, Tupou, Luke Keary, Joseph Manu and James Tedesco all crossed in a rampant first half for the hosts, who lost Boyd Cordner to a head injury after 26 minutes, though tries from Enari Tuala and Gehamat Shibasaki ensured the Knights were not completely out of the game.

The Roosters moved the ball magnificently for Tupou to touch down for the 100th time in the left corner three minutes after the restart, and Jake Friend's excellent pass preceded Keary completing his double in the 70th minute.

Brett Morris and Joseph Manu held up Lee to keep Newcastle, who were without full-back Kalyn Pogna, scoreless in the second half, with Sonny Bill Williams playing over half an hour after managing 14 minutes on his debut last week.

The Roosters' success meant Canberra Raiders remain two points adrift of the top four despite a big 37-8 win over St George Illawarra Dragons.

Jack Wighton touched down twice for the visitors at WIN Stadium, while Hudson Young, who missed last year's Grand Final due to an eight-game ban for eye gouging and suffered a serious knee injury in pre-season, scored a try and set one up for John Bateman.

Young's display enabled Josh Papalii to rest for the entire second half, with the only consolation for the Dragons being Cody Ramsey scoring with his first touch in NRL and adding a second before half-time.

Brisbane Broncos took the lead against Gold Coast Titans but ended up succumbing to a club-record ninth straight defeat.

Darius Boyd put the struggling Broncos ahead at Cbus Super Stadium but after Ash Taylor's line break initiated a length-of-the-field move that was finished off by Young Tonumaipea, the Titans held firm for an 18-6 triumph.