Ricky Walden defeated Shaun Murphy 3-1 boosted by a glorious closing break of 135 to top Group G and qualify for the final day of the Championship League.
He was joined in the last eight on Friday by Belgium's leading player Luca Brecel, who also went through his day unbeaten in winning Group B on seven points.
Murphy made breaks of 59, 100 and 112 to overcome Elliott Slessor 3-1 in his section opener before knocks of 64 and 88 helped him eclipse Anthony Hamilton, who compiled 106 in the second frame.
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The 2005 world champion needed only a point against Walden in the group decider and looked on course when he made 62 in the third frame at 1-1, but missed a red to leave Walden needing a snooker as his opponent recovered to pinch it by three points (65-62).
A clinical closing 135 finished off his Thursday in style after a 2-2 draw with Hamilton and 3-1 win over Slessor earlier in the day had left him needing three points against Murphy to stay alive.
“When I finished off, that’s the best frame I’ve played all day," said Walden, who is back up to 18 in the world after a series of back problems in recent times. "It’s been a bit of a slog at times and I rode my luck at times.
I got lucky at the end and put a good break together. I thought I was done. I was 5o odd down and I thought I had to go for something.
"I didn’t want to be driving home on the back of a safety shot. You get used to winning games. I didn’t play well today, but luck has been with me.
“The next one I win will be the best one I’ve won from where I’ve come from.”
Brecel stayed on course to claim a second Championship League title in the past three years after drawing 2-2 with Daniel Wells in his first match of the day.
He added a break of 91 in a 3-0 victory against Jamie Clarke before restricting Chris Wakelin to only 44 points as runs of 114, 80 and 63 secured his progress.
Wakelin enjoyed breaks of 139 and 108 in holding Wells to a 2-2 draw, a result that saw Wells finish second in the group on five points after he closed with a 3-0 win against fellow Welshman Clarke, making breaks of 51 and 79 to maintain an impressive level of consistency.
Brecel, Zhao Xintong, Xiao Guodong and Lyu Haotian will contest Group 1 with Walden, Stuart Bingham, Lu Ning and Pang Junxu competing in Group 2 of the third group stage.
The two group winners will contest the final of the season's first ranking event on Friday night.
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