O'Sullivan completed a 10-1 victory over Thailand's Thepchaiya Un-Nooh in 108 minutes, comfortably beating the previous record of 149 minutes held by England's Shaun Murphy, for winning a best-of-19 frames match at the tournament.

Leading 8-1 from yesterday's first session, O'Sullivan needed less than half an hour's play to wrap up a comprehensive victory, winning frame ten with a break of 93 and the final frame with two breaks in the forties.

The two other matches that concluded on day four were much lengthier but equally exciting affairs.

In a match that lasted more than five hours, England's Jack Lisowski was taken all the way by Scotland's Anthony McGill, losing a dramatic final frame that was decided by a lengthy safety exchange on the blue.

Scotland's McGill led 5-4 after the morning's opening session, and extended his lead in the evening session.

Thirteenth seed Lisowski battled back to force a decider, but eventually lost 10-9.

The day's other result saw Yan Bingtao of China survive a fightback from England's Elliot Slessor to win 10-7.

China's Bingtao, the 16th seed, held a 7-1 advantage from the first session and extended his lead to 8-1 and 9-2.

Slessor fought his way back winning two dramatic frames in the process, taking the 13th on the black and the 14th after Bingtao committed a foul on the match ball green by potting the black on the same shot.

After the Englishman closed the gap to two frames Bingtao took a tightly contested 17th frame to get over the line in a contest that lasted more than six hours.

Two former world champions were in action in the day's other matches, which are played to a finish tomorrow.

England's Shaun Murphy, the 10th seed, trails Thailand's Noppon Saengkham 6-3, while England's Mark Selby, the seventh seed, leads Northern Ireland's Jordan Brown 5-4.

In tomorrow's other matches, Northern Ireland's Mark Allen, the fourth seed, faces Wales' Jamie Clarke, Scotland's Stephen Maguire, the ninth seed, faces England's Martin Gould and England's Barry Hawkins, the 15th seed, faces Switzerland's Alexander Ursenbacher.

The tournament is currently being played behind closed doors because of restrictions imposed by the United Kingdom Government to contain the coronavirus pandemic.

In an attempt to replicate some of the missing atmosphere, organisers have started playing recorded applause in the arena at the end of frames or at significant moments.