O'Sullivan began the 2005–06 season at the Grand Prix, and reached the final, but lost 2–9 against John Higgins. In his last-32 match with Mark King at the UK Championship, O'Sullivan sat with a wet towel draped over his head for most of the contest, and lost 8–9. He then successfully defended his Premier League title. Having finished first in the league stage, he defeated Steve Davis 5–3 in the semi-finals, and Stephen Hendry 6–0 in the final. O'Sullivan then reached the final of the Masters, but lost 9–10 against Higgins. In the deciding frame, he scored 60 points ahead before losing the vital red and Higgins, made a 64 clearance to win the match. O'Sullivan skipped the Malta Cup, and then lost his opening matches at the next two ranking events, as he lost 1–5 against Ian McCulloch at the Welsh Open and 0–5 against James Wattana at the China Open.