The Dutchman, who retired in 2020 but made his comeback in February having gone through qualifying school, found himself 8-3 down in his first televised quarter-final in three years.
However, he rallied with seven successive legs and never looked back as his 20th 140 and his sixth maximum then saw him move 13-10 ahead and a 10th leg in 12 edged him close to victory before holding off a late fightback from the three-time defending champion.
“He played amazing in the first 10 legs. I’m not playing bad and I will never give up and I promised my grandson today,” Van Barneveld, who won the Grand Slam title a decade ago, told Sky Sports.
BRILLIANT BARNEY! 👏
Astonishing scenes in Wolverhampton, as Raymond van Barneveld recovers from 8-3 down to dump out reigning champion Gerwyn Price and secure his place in the Grand Slam semi-finals!#GSOD | QF pic.twitter.com/p8ih8Q3hTd
— PDC Darts (@OfficialPDC) November 18, 2022
“8-3 down and I’m thinking ‘OK Ray, win a couple more legs against the world number one’ and then it changed.
“It’s all about belief and I worked unbelievably hard. I was struggling for many years and now with Julia (Evans) we’re going to marry next year. She’s the love of my life and I’m happy.”
In the opening quarter-final Michael Smith won a last-leg decider for a roller-coaster 16-15 victory over Joe Cullen.
The two-time world championship runner-up was never behind until his opponent edged ahead 10-9 and then 13-10.
But he went on to win six of the final eight legs to snatch victory with a 76 checkout, finishing with a 100 average having posted 14 180s.