Gary Anderson kept up his hopes of winning a third world championship, but required a new look to do so.
The Flying Scotsman opted to change both his glasses and darts after struggling to find form early on against Rob Cross.
It's clearly a tactic that worked for the 2015 and 2016 champion, with the 51-year-old going on to hit seven 180s and averaging 97.27 to beat Cross 4-3.
In doing so, Anderson progresses to the quarter-finals, the seventh time he has done so in eight years.
Speaking of the changes he made, Anderson said, "I went back to the old darts and they were working a treat. I was doing all right. I was 3-1 up and made a complete mess of one leg.
"Rob stuck in and came back. But there were no nerves.
"I win and it's fantastic to get through. If I get beat I go home and spend a few extra days with the family. No pressure whatsoever."
It was Cross who claimed the first set of the match, before Anderson rallied to win five successive legs, helped along the way by a 170 checkout that sealed a 3-1 lead.
Anderson had the chance to take a 2-0 lead in the fifth set but missed seven darts at the double, allowing Cross to produce an impressive 144 checkout and storm back to level proceedings.
However, Anderson kept his nerve at the Alexandra Palace and dominated the last set to secure a quarter-final tie with Luke Humphries.
Elsewhere in the tournament, Peter Wright took out Ryan Searle, with the Scot progressing after a 4-1 win which included seven 180s and 20 140s.
The pair met in the decider of the Players Championship Finals last month, which Wright edged 11-10.
But it was far more straightforward for Wright this time with his third-set average of 102 ending Searle's hopes of mounting a comeback.
James Wade also made his way to the last eight after a 4-0 win over Martijn Kleermaker - he'll now face Mervyn King in the next round.
The Dutchman won only four legs as Wade moved to within one victory of a fourth World Championship semi-final appearance.
In the afternoon session, King and Humphries booked their places in the next round, with both recovering from deficits to claim wins over Raymond Smith and Chris Dobey.
Finally, Callan Rydz lost his first set of the tournament, but the 23-year-old recovered well to make the quarter-finals for the first time.
He'll now face Alan Soutar in the last eight.