World Championship snooker: Ronnie O'Sullivan beats Mark Williams; Kyren Wilson sees off Judd Trump; Mark Selby thumps Neil Robertson

O'Sullivan began the day trailing 6-2 and with a mountain to climb, but produced a display that didn't always show him at his brilliant best. It saw him fight tooth and nail to scrap his way back into the contest in the afternoon before hauling himself over the winning line in the evening session with a blitz that left Williams bereft of answers.

O'Sullivan would have surely feared the worst when seeing Williams pick his pocket in the opening frame of the day, a break of 54 not enough to stop him slipping 7-2 behind, before he rallied to win two of the next three frames before the mid-session interval.

Williams was still in ascendancy at the break when nursing his 8-4 lead but O'Sullivan would not be bowed, digging in to the claim the next two frames before breaks of 112 and 54 saw him finish the session with a flourish and level the scores at 8-8.

If the afternoon session saw O'Sullivan showcase a great will to win and a desire to progress to the semi-finals that bordered on desperation, the evening session was much closer to vintage O'Sullivan as he reeled off breaks of 52, 104, 61, 65 and 133 to win five of the seven frames in just over two hours.

Williams actually struck first in the evening as O'Sullivan failed to capitalise on a sizzling opening long red and left the door ajar for Williams to inch back in front.

O'Sullivan was again in first in frame 18 but slammed his cue in frustration when breaking down amongst the balls, a miss that sparked a series of unforced errors from both players as the magnitude of the frame and match began to take effect.

In the end, O'Sullivan finally managed to put the frame to bed and looked sure to take the lead for the first time since the third frame, when cruising to 52 in the following frame before again breaking down.

Williams quickly whittled down his deficit but the frame was turned on its head when the Welshman fluked a snooker having missed an audacious double on the final red, one he would eventually pot to win the frame.

Despite that setback - one of any number in the match - O'Sullivan wouldn't back down and when Williams missed a pink early in frame 20, the Rocket produced a wonderful run of 104 to level the scores once more at 10-10.

As the players headed for the final mid-session interval, a tense finish seemed almost inevitable, but O'Sullivan had other ideas and a timely fluke when a wayward attempted pot flicked another red on the way into the yellow pocket paved the way for a break of 61.

It wasn't enough to clinch the frame but there was nothing wayward about the long red O'Sullivan found moments later and he cleared to the black for a run of 65 that suggested the momentum of the match had shifted.

Indeed it had and, as Williams' long game began to falter under the pressure, his opponent smelt blood and pounced in predator-like fashion.

A missed red from distance at the beginning of frame 22 saw Williams grimace as he headed back to his chair but not even he could have predicted that within a matter of minutes O'Sullivan would have cleared the table.

It was a break of a pure genius; O'Sullivan determined not to let his chance slip as he struck the ball with an ever-increasing authority, a dangerous plant pulled off with an air of arrogance before he split the reds and went about his work like a surgeon.

When the final black was slammed into the corner pocket, the clearance of 133 complete, Williams could be seen tapping his cue on the floor in appreciation.

There was still time for more drama as both players made more unforced errors in a 23rd frame that O'Sullivan should have wrapped up but somehow missed match-ball; a simple blue that left him smiling and cursing in equal measure.

Williams negotiated the final three colours to force a re-spotted black but it was O'Sullivan who had the final say, potting from distance and setting up a semi-final with old rival Mark Selby.

Afterwards, O'Sullivan played down his chances of winning a sixth world title: "I'm not hard on myself, I'm a realist. I'm not doubting that I've got ability. What I'm good at I'm unbelievably good at: my scoring, my break building, my positional play.

"There will always be a little bit like... Maradona. You look at him now, he's big and fat but you put a ball at his feet and the geezer's unbelievable - but he's not fit enough to play against guys who haven't got as much talent as him.

"It's a little bit like snooker. You've got to have the long game and the safety and the cue action, you've got to have the reliability.

"I don't believe you can win it being good or rubbish, and I've been good or rubbish. I just need to be steady. Otherwise it's like trying to win the US Open with a five-iron in my bag.

Of his semi-final opponent, he added: "I love Mark Selby, he's my favourite guy on the circuit. He's proper lovely guy, funny as hell, but as a snooker player he's a beast and the ultimate test, and I'm going to have to draw on every bit of skill and experience that I've got."

Wilson ends Trump's title defence

Kyren Wilson got the better of rival and defending champion Judd Trump to reach the semi-finals of the World Championship.

Leading 10-6 overnight, Wilson saw his advantage eaten into at 11-9, but responded in the style of someone ready to conquer the world as he took the next two frames in a 13-9 victory.

Trump had been made to work hard in the first two rounds and came unstuck against his fresher opponent, who had received a bye when Anthony Hamilton withdrew on the eve of the tournament.

Still, Wilson deserves great credit for gaining revenge over Trump, who edged him out in a high-quality tussle for the Gibraltar Open in the final event before the sport ground to a halt in the spring.

Trump had a mountain to climb on Tuesday but it was clear early on that he meant business, breaks of 72, 100 and 62 enough for him to take the mini-session 3-1 and cut his deficit in half.

Wilson had looked in good nick with a 94 break to edge closer to the magic 13 frames required, but he'd failed to score in the other three and it appeared vital that he stopped the bleeding when the players returned following a short break.

That's exactly what he did, this time denying Trump a single point to get within one, before a sublime 104 break sealed a deserved win, and a semi-final meeting with Anthony McGill after the Scot withstood a spirited fightback from Kurt Maflin to triumph 13-10.

"I wasn't lying when I said I was looking forward to playing Judd here," said Wilson. "Reigning world champion, world number one... if you can't get up for a match like that you'll never get up for anything.

"You want to see where your game's at, and obviously we've seen that (mine) is not in bad shape.

"What a reign as a world champion he's had - he's set the benchmark for the rest of us. It's definitely up there with one of the better wins of my career."

Trump refused to accept that he'd lost some of his momentum since lockdown, saying: "I didn't see it like that. I know a lot of people were saying I wasn't playing my best, but I was quite happy with how I was playing.

"I didn't play amazing last season. I was more than happy with my form on the practice table and even in that game I felt good, it was just a lot of things happening at the wrong times out there that really did change the game. Just bits of luck you need to win the tournament which weren't going my way."

Selby steamrollers Robbo

Mark Selby beat Neil Robertson 13-7 to become the first player to reach the semi-finals of the World Championship.

The three-time world champion had taken the final two frames of a lengthy and at times brutal session on Monday evening to earn a commanding 11-5 advantage, and he rarely looked like letting it slip.

A 91 break to begin on Tuesday morning got him within one and though a shocking miss in the following frame allowed Robertson in to steal it, already it was clear that the match was beyond him.

The Australian took the next to get back within five but his failure to make more than a 53 break in the next allowed Selby to pinch it, albeit in fairly ragged fashion, and reach the last four.

There he will meet old rival O'Sullivan for a place in the final.

Selby, who was forced to battle through the first two rounds against Jordan Brown and Noppon Saengkham respectively, believes the manner of his win over fellow former champion Robertson indicates he is back to somewhere approaching his best.

The 37-year-old said: "Over the last 12 to 18 months I was questioning myself. I had got so used to winning tournaments than when I wasn't winning tournaments it became very damaging to my confidence.

"I was happy with my performance against Neil. I felt if I got a chance I could score, and my safety play was back up with how it was a few years ago.

"As a match-play game it was right up there with my best performances. I can see the changes already, especially in my body language, so long may it continue."

Robertson was left to rue a series of tight frames which went against him as his search for a second world title extends beyond a decade.

He said: "It was a really tough game and apart from three or four frames in the match, every frame came down to the final few reds or the colours.

"Mark's defensive safety was absolutely unbelievable. He didn't let up really and I think he got his game plan spot-on over over the two days.

"He kept it super-tight and I couldn't get any free-flowing scoring going at all."

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