Ronnie O'Sullivan leads John Higgins 9-7 in World Championship second-round clash at the Crucible

O'Sullivan dominated Saturday night's opening session to lead 6-2, and looked to be moving towards a swift conclusion when pulling 9-4 ahead thanks to breaks of 116, 80 and 91.

However, Higgins rallied in typically determined fashion, winning the last three frames of Sunday night's second session to set up a thrilling finale on Monday.

A run of 71 helped the Scot reduce his arrears to 9-5, despite a late scare when snared by an O'Sullivan snooker, and he held his nerve to take out the next frame on the final black.

O'Sullivan appeared to be in control of the final frame of the session, but a wrap of his knuckles on the table when missing a tricky red suggested he was beginning to feel the heat, and his mood was made worse when he went in-off when later potting the final red.

Higgins duly stepped up to clear to the pink, breathing new life into a match that is simmering towards a thrilling conclusion.

On the other table, Wu Yize leads four-time champion Mark Selby 9-7.

Selby started like a train, opening with back-to-back centuries, but Wu competed hard in the safety department across the two sessions played on Sunday, and holds a slender advantage going into Monday's final session.

Zhao through to last eight

Earlier, Zhao Xintong saw off compatriot Ding Junhui 13-9 to book his place in the quarter-finals.

Zhao resumed leading 9-7, and was always able to keep his opponent at arms length, setting up a mouthwatering tie with Shaun Murphy.

Zhao told World Snooker Tour: "Before the match I said I just wanted to enjoy it and not put myself under pressure.

"It wasn't like that. We knew everyone had their eyes on us. I couldn't enjoy it.

"I am really happy I won though, and when we finished I talked with Ding and he just said to keep going.

"I know Shaun Murphy is a very good attacking player. Hopefully we have a very good game.

"Please tell him, no safety! All out attack."

Judd Trump again looked sharp as he carved out a 9-7 advantage over Hossein Vafaei in a match featuring a number of big breaks, while Neil Robertson has one foot in the last eight, leading Chris Wakelin 10-6.