Ronnie O'Sullivan labelled Si Juahui's performance "poor" after beating the Chinese star to reach the semi-final of the World Snooker Championship. The seven-time world champion held off a fightback from his opponent in the evening session to win 13-9 and set up a clash with Zhao Xintong.

O'Sullivan led 10-6 after the afternoon session, only for Si to take three of the next four frames to reduce the deficit to 11-9. However, the 22-year-old then missed chances in each of the final two frames and 'The Rocket' capitalised to keep his hopes of an unprecedented eighth world title alive. Afterwards, though, he focused on Si's mistakes and was also critical of his own form.

"He played poor," O'Sullivan told the BBC. "He played poor the whole match and let me off the hook loads of times. I got lucky again. He had lots of chances, I was trying everything and he let me off the hook."

O'Sullivan has ended a three-month exile from the sport to compete in Sheffield. Throughout the tournament, he's played down his form and revealed he had made a key alteration before his latest match.

"I'm just grinding it out," he continued. "I had some work done on my cue today, I am playing awful and my cue feels awful but I am still here. I miss the buzz of playing well.

"I have given it my best but I am hanging in there. I would like to be playing better but I have to try and find some form at some point. I don't feel rusty, I have only been playing for a month but I just couldn't face playing."

If the 49-year-old beats Xintong, he will face either world No.1 Judd Trump or Mark Williams in the final. Both players came through high-quality quarter-final matches against Luca Brecel and John Higgins respectively, and O'Sullivan namechecked Trump when reiterating he had to up his own game.

"It gets harder, look at the way Judd is playing," he said. "I won't be able to get away with what I have done so far. I can't get any worse, put it that way."