Mitchell Aubusson scored a try in his 300th NRL appearance as the in-form Sydney Roosters beat St George Illawarra Dragons 24-16 on Thursday.

Aubusson became only the 40th player to reach the landmark and the one-club man marked the occasion in style, scoring the second of five Roosters tries at WIN Stadium.

Joseph Manu crossed in the first minute in Wollongong and Aubusson crashed over to put the two-time defending premiers 10-0 up after 13 minutes.

The Dragons, reeling from back-to-back defeats, hit back and were level at the break following a double from Zac Lomax, who converted one of his scores.

Luke Keary starred in the second half, laying on a try for Sitili Tupouniua and scoring one of his own after Manu dotted down for his second of the night.

Matt Dufty scored a third Dragons try in the closing stages, but the Roosters had a third consecutive win in a row in the bag by then to sit three points behind leaders Penrith Panthers, in fourth place.