Dutchman Raymond van Barneveld beat Michael Smith in a tie-break to reach the PDC World Championship semi-finals at Alexandra Palace.
The five-time world champion fought back from losing the first three sets to win four legs to two in the decider.
He will play fifth seed Adrian Lewis on Saturday, the Englishman having beaten Scotland's Peter Wright 5-2.
In the other semi-final, 2015 champion Gary Anderson will play unseeded Dutchman Jelle Klaasen.
Scotland's Anderson averaged 105 as he demolished three-time semi-finalist James Wade 5-1 in the afternoon session, while Klaasen recovered from a 3-1 deficit to beat Alan Norris 5-4.
Number one seed Van Barneveld, 48, had knocked out world number one Michael van Gerwen in the last 16, but he looked out of sorts as eighth seed Smith dominated the early stages of their quarter-final to take a 3-0 lead.
The Dutchman had been having problems hitting his doubles, but eventually found his range to win 12 out of 14 legs to take a 4-3 lead, including a 110 average in the sixth set.