Mark Allen got through to the Masters quarter-finals after emerging from a high-quality contest with former winner John Higgins.
The Antrim man was a 6-4 victor at Alexandra Palace but the scoreline did not tell the story of an outstanding tussle.
The pair put on three centuries in the three opening frames, with another following later, as well as breaks of 96 and 88. Higgins also missed out on two maximum breaks, with one attempt faltering on the final yellow.
It was a tough afternoon for the Scot, who scored 668 points but found himself on the wrong end of the result.
His slip-up on 120 in the ninth frame was the stand-out moment of misfortune, though. Attempting to match Marco Fu's 147 on Sunday, he did not get high enough up for the yellow and had to take on a mid-ranger which rattled the jaws and spun out.
"John has done most of the scoring," Allen, who posted a personal high of 121, told BBC 2.
"I have a good record against him recently and I just needed to hang in there. I stayed positive and did that.
"I was edgy early on, like I am in any match, but I like to think I'm pretty good under pressure."
Allen has put himself on a strict fitness regime in 2015, restricting intake of carbohydrates to just Sundays, in a bid to be more nimble around the table.
"There's certain shots out there which I can't reach, I'm too fat," he added. "I need to lose weight."
There was a surprise in the second game of the day as Joe Perry knocked out Ding Junhui, another former winner.
It was not as fluent an affair as the Allen-Higgins one, although there were two century breaks, both of which went the way of Perry.
The Cambridge man kept his nerve when it mattered and was a deserved 6-3 winner, with Ding never looking like getting going.