Zhao Xintong moved closer to cracking the so-called “Crucible Curse” as he booked his quarter-final place at the World Snooker Championship, wrapping up a hard-fought 13-9 win over compatriot Ding Junhui.

The defending champion shrugged off some evident nerves to build on a 9-7 overnight advantage despite losing an error-strewn, 46-minute opener that saw Ding temporarily reduce the arrears to a single frame.

The 29-year-old – who is looking to become the only first-time winner to retain his title at the Crucible – capitalised on a series of misses by his opponent to pull away. Zhao produced a break of 108 in the penultimate frame as he set up a last-eight clash with Shaun Murphy.

“Today I think there was more pressure,” Zhao told BBC Sport. “I know Ding didn’t play very well in the last session, but the pressure is very big. This year I just don’t want to lose any match, so it feels very different.”

Mark Selby started off with two centuries but was forced to fight back from behind to ensure the opening session of his second-round match against No 10 seed Wu Yize ended all-square at 4-4.

Four-time world champion Selby threatened to overwhelm his 22-year-old opponent with breaks of 124 and 129 in the first two frames, but Wu summoned a brilliant response by reeling off the next three in a row in a high-quality session.

The duo split the next two before Wu’s early sniff at a 147 was ended by a bad kick on a red. Selby reeled in a 44-point deficit to ensure they will return for the second session on Sunday evening level at 4-4.

On Sunday afternoon, Neil Robertson and Chris Wakelin resume all-square at 4-4, with Judd Trump’s match against qualifier Hossein Vafaei poised at the same score. Ronnie O’Sullivan takes a 6-2 lead into his evening session against John Higgins.