The five-time world champion has spent most of the week debating the future of the sport - while not always being supporting of its governing body, World Snooker - but has taken none of that on the table with him.
He beat Tom Ford 4-0 in the afternoon to make the last 16 and then saw off Zhou Yuelong 4-1, taking his career centuries tally to 973 in the process.
O’Sullivan plays David Gilbert in the quarters after his win over Lu Ning, while Mark Selby beat Martin O’Donnell to tee up a clash with Thepchaiya Un-Nooh.
Judd Trump beat Luca Brecel 4-2 to book his place, while the evergreen Peter Ebdon remains a dangerous opponent, beating Li Hang 4-1.
Earlier, Sanderson Lam suffered a third-round exit in Belfast.
The 24-year-old Leeds cueman had enjoyed his best run in a tournament this season after wins over Joe O’Connor and Sean O’Sullivan.
But he lost 4-1 to Robbie Williams - who had knocked out fellow Leeds potter Peter Lines 24 hours earlier.
The pair shared the opening two frames, but in a low-scoring contest, Williams emerged as winner.