The World Championship last-16 tie between Ronnie O'Sullivan and John Higgins is set for a thrilling finish on Monday after the Scot won the last three frames of the second session to close the deficit to only two.

Seven-time Crucible winner O'Sullivan led 6-2 following Saturday's first session and the match looked over when he stretched that advantage to 9-4 in the first-to-13 clash.

But fellow 'Class of 92' member Higgins, with four world titles himself, fought back on a night of high drama to leave O'Sullivan 9-7 ahead, needing four more to claim victory.

The tension appeared to get to O'Sullivan in the final frame of the session when he punched the table in frustration, having missed a pot on a red.

"That is exactly what it means to Ronnie O'Sullivan," said 1997 world champion and BBC commentator Ken Doherty. "He's getting frustrated. He had a great chance in the previous frame and didn't convert. Those knuckles will be sore, let me tell you."

O'Sullivan and Higgins, who are both 50, play the final session of an enthralling match from 13:00 BST on Monday, live on BBC Two.

"John has been incredible and it is incredible he is in this match," said seven-time world champion Stephen Hendry. "Last night [in Saturday's first session] he really struggled for whatever reason.

"Ronnie's play was outstanding but John seemed really un-Higgins like. Maybe it was a little bit of nerves, a bit of intimidation, but he has just battled to stay in this match. Ronnie did not look the same player."

After a break of 83 from Higgins in the ninth frame, O'Sullivan won two in a row, thanks to runs of 116 and 80, to hold a dominant five-frame advantage at 8-3.

Higgins won the 12th, but O'Sullivan's break of 91 left the Englishman 9-4 in front.

But the final three frames were very dramatic. Higgins looked in control of the 14th, with O'Sullivan needing a snooker to have any chance, which he then got, although he could not capitalise.

Higgins took the 15th on a black-ball finish, with O'Sullivan then hitting the table early on in the last frame of the night.

His mood was not improved when he potted a long red but then saw the cue ball follow it into the same pocket, with that foul proving crucial as Higgins took the frame to give himself some hope.

O'Sullivan is fighting to make the Crucible quarter-finals for a 24th time and looking for an eighth world title, which would be a record in the modern era.

He was watched by former Manchester United footballer Paul Scholes during his 10-2 first-round win over Chinese debutant He Guoqiang and, this time, UFC fighter Paddy Pimblett and Liverpool defender Milos Kerkez were in attendance.

They, along with the rest of the crowd at the Crucible, would have left thoroughly entertained.

World number one Judd Trump holds a 9-7 lead over Iran's Hossein Vafaei with one session to go.

It was level at 4-4 after Saturday's opening session and Vafaei, 32nd in the rankings and the only qualifier to make it past round one, won the first frame on Sunday, only for Trump to take the next two.

Breaks of 82 and 65 restored Vafaei's lead, but 2019 winner Trump won the final three frames, making runs of 100, 74 and 94, to hold a two-frame advantage before it is played to a finish on Monday (19:00).

Another former champion, Australian Neil Robertson, the 2010 winner, also has a lead going into Monday's final session against England's Chris Wakelin.

That was another match that was at 4-4 at the beginning of Sunday, with world number three Robertson winning six of the eight frames, including a 101 break in the final frame, to lead 10-6.

Four-time Crucible winner Mark Selby will have to come from 9-7 down if he is to make the quarter-finals against 22-year-old Chinese player Wu Yize, the youngest player left in the tournament.

Selby made a superb start - with breaks of 123 and 124 - to go 2-0 ahead, but world number 10 Wu turned things around, although Selby took a vital last frame thanks to a break of 81.

That match will be played to a finish on Monday (13:00).

China's reigning champion Zhao Xintong defeated compatriot Ding Junhui 13-9 in a high-quality encounter to move into the 2026 World Championship quarter-finals.

Zhao, 29, began the final session with a 9-7 advantage although 39-year-old Ding, the first Chinese player to win a ranking event, pulled one back by winning a 46-minute opening frame on Sunday.

However, Zhao then won the next two to move 11-8 ahead, before Ding took the 20th frame with a break of 76.

A break of 108 from Zhao, his third century of the match, took him to the brink and he sealed the win in the next frame.

Zhao, who also made five half-centuries, is trying to break the so-called 'Crucible Curse', which stems from the surprising fact that none of the previous 20 first-time winners of the World Championship in Sheffield have successfully retained the title the following year.

He will play 2005 champion Shaun Murphy next.

Such was the interest in the match between Ding and Zhao in China that Jason Ferguson, chairman of the World Professional Billiards and Snooker Association, suggested that "hundreds of millions" could be watching.

"This was a very special match for us that everybody knows about and wants to keep eyes on it," said Zhao. "There was more pressure, it is not like before.

"It was very different last year when I was a nobody guy, but now I don't want to lose any match and just want to keep going."

On his quarter-final with Murphy, Zhao added: "When he won the World Championship I was eight years old. When I was eight I saw him play with Ding many times and I know he's very good and still plays very good snooker.

"I will try my best. I'm far from my best."

Ding, the 2016 runner-up, made eight breaks of at least 54 in the match but was unhappy with his performance.

"It was not good enough, I was a little bit disappointed in the first two sessions," said Ding. "He [Zhao] is doing well and he is improving every time. My thought is he is better than anyone."