Talented 21-year-old Lines beat Judd Trump 6-2 in the previous round and kept his momentum going with another excellent display against Robertson, knocking in breaks of 90, 51, 67 and 72.
The world number 61 from Leeds is through to the last 16 of a ranking event for the second time in his career and now meets Marco Fu on Wednesday evening.
“If I had lost today after beating Judd the other night then it wouldn’t have meant much,” said Lines, who won the Rookie of the Year award after his debut season in 2014/15. “Judd actually messaged me before the match today and said I better not lose.
“I played really well and handled the occasion. I have been working on my scoring and I made good breaks at the right times today.
“Hopefully this is the start of something good. I remember when David Grace got to the semi-finals here last year, and I said to my dad ‘that will be me next year.’ It will be tough against Marco Fu though because he is world class.”
Oliver’s dad Peter lost to Liam Highfield last night, ending their dream of a semi-final meeting, but it has still been a lucrative week for the family, with £25,000 in prize money already banked. “I keep getting texts off my sisters saying what they want for Christmas,” joked Lines Jnr. “I’m really proud of what me and my dad have done here.”
Shaun Murphy came through a dramatic tussle with Dominic Dale, winning 6-5 to earn a match with Zhou Yuelong. Murphy, the 2008 UK Champion, built a 5-2 lead with top breaks of 63, 89, 65 and 103. Dale battled back to 5-5 and looked favourite in the decider until he missed a red to a top corner leading 34-15. Murphy seized his chance with a 34 clearance.
“I missed chances to win at 5-2, 5-3, 5-4, and it really didn’t look like I deserved to win the game in the end as I was making mistake after mistake,” said Murphy. “I wasn’t able to get to the line and think clearly. I made a mistake at 5-2 and punished myself throughout the next few frames. I wasn’t able to put one foot in front of the other.
“It’s a horrible feeling, thinking you’ve messed it up, and it’s very hard to play through. Dominic commented on the number of chances we both had at the end there. We made that look very difficult out there – snooker can do funny things to you. Maybe the trick is not to care and got out and play with a bit of freedom, but my problem is that I do care.”
“I’m just pleased to still be here and have the problem of wondering where to go to dinner in York this evening. That’s a nice problem to have, rather than to have to drive home down the A1 after another disappointing, devastating loss. I’m 34 now and I’ve been doing it a long time, but every defeat still hurts, and that disease-ridden feeling of loss started to circle then.”
Mark Williams also came out on the right side of a 6-5 scoreline, beating Ricky Walden. Chester’s Walden led 5-3 with a top break of 86 but he missed chances in the next two frames and two-time UK Champion Williams eventually won the tie with a run of 91 in the decider. The result means that Walden will miss the Masters for the first time since 2012, having dropped out of the world’s top 16. Williams now meets :Liam Highfield.
Matthew Stevens set up a match with Ronnie O’Sullivan by beating Joe Perry 6-2. Welshman Stevens, the 2003 UK Champion, compiled beaks of 64, 57, 93 and 61.