Ronnie O'Sullivan leads Si Jiahui 6-2 in World Snooker Championship quarter-final at the Crucible

O'Sullivan has been left frustrated by his lack of form in earlier wins over Ali Carter and Pang Junxu, and he was far from foot-perfect here.

However, Si turned in a generally ragged display himself, making a host of unforced errors and quickly falling 5-1 behind despite compiling a polished century in frame two.

O'Sullivan continued to feed off his opponent's mistakes, still proving devilishly ruthless when let loose in the balls, and there were signs he was slowly working through the gears as the session wore on.

Breaks of 71, 54 and 87 had done the early damage for O'Sullivan, but after Si pulled a frame back to trail 5-2, the Chinese missed a trick when losing the seventh frame from 52-0 in front.

O'Sullivan duly made him pay with a trademark counter of 67, and the seven-time world champion then ended the session with a sublime 121 to put himself in a strong position ahead of Wednesday's resumption.

Fireworks from Trump and Brecel

On the other table, the predicted fireworks from Judd Trump and Luca Brecel most definitely materialised, the pair trading three centuries and a series of other big breaks in a breathless opening session.

Trump had threatened to steal a march on the 2023 champion when powering 5-1 ahead, but Brecel stepped in with a crucial clearance of 68 in frame seven, before finishing with a spectacular 128 clearance to end the session only two frames adrift.

Higgins and Williams all sqaure

After two sessions of play, John Higgins and Mark Williams are locked together at 8-8.

The two all-time greats were greeted to a special reception at the start of their eagerly-anticipated last-eight clash, and they look set to deliver a grandstand finish on Wednesday morning.

Higgins made the early running, moving 5-1 ahead, before Williams produced breaks of 104 and 59 to win the final two frames of the opening session.

In the evening, it was roles reversed as Williams threatened to take charge, moving 7-6 in front, only for Higgins to win two of the last three frames to level the scores in the race to 13.

Elsewhere, Chris Wakelin finds himself staring at the exit door, currently trailing Zhao Xintong 12-4.

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