Cameron Menzies needed medical attention after being taken ill during his World Matchplay second-round match against Ross Smith in Blackpool on Wednesday.
While leading the game 2-1, Scotland’s Menzies stepped away from the oche and appeared unsteady on his feet as England’s Smith and the referee guided him safely off stage.
It was later confirmed that Menzies was cleared by medics backstage but was unable to return to the stage to continue, and so forfeited the match.
The PDC said: “Cameron experienced high blood pressure, which caused him to feel dizzy and subsequently faint.
“Following an assessment by the on-site medical team, Cameron was deemed well enough to return to his accommodation.
“We wish Cameron all the best and look forward to seeing him back in action soon.”
Elsewhere, seventh seed Gerwyn Price knocked out fellow former world champion Ross Cross with a dominant display.
From 2-3 down, the Welshman won six legs in a row to take control of the match and then eased to an 11-5 win to set up a quarter-final match with Smith.
World number three Gian van Veen booked his quarter-final spot by overcoming fellow Dutchman Wessel Nijman in a tie-break.
In a back-and-forth encounter, both players landed 100-plus checkouts to prolong the match but it was Van Veen who came out on top 14-12 in a thriller.
Sixth seed James Wade completed the last-eight line-up at the Matchplay with a comfortable victory over fellow Englishman Ryan Searle, the 11th seed.
Wade, who won the competition in 2007, will take on Van Veen in his 14th Matchplay quarter-final after the 11-8 win.