William O'Connor described the bias of the seeding system at the 2026 BetVictor World Cup as "absolutely rubbish" after the Republic of Ireland started their campaign with victory.
The four highest ranked countries based on their individual PDC world ranking advance straight into the second round, with England, the Netherlands, Northern Ireland and Scotland occupying those slots.
O'Connor, a former finalist in this competition in 2019, partnered Mickey Mansell in Ireland's Group D opener against Singapore and prevailed 4-1 to put themselves in pole position of progressing in Frankfurt.
However, the 39-year-old believes all the teams should be on a level playing field for the global event.
"In a short format, first to four [legs], you could pick two guys out of the pub and could turn around and win this," O'Connor said.
"I'm not just saying it, but it's a good job that those boys that are seeded are into the second round because I don't think the four [teams] would come through.
"Put those boys into the same round as us. I think everyone in the World Cup should be in the same draw.
"It's the World Cup, every single person in the world should be in the same draw. England, Scotland, Northern Ireland, I don't care who they are.
"It's ridiculous [that they enter in the] second round of the World Cup. I don't agree with that. I think it's absolutely rubbish.
"Put those boys into the same round as us and see how they do under pressure, because we were under serious pressure today."
Singapore moved ahead thanks to Phuay Wei Tan's brilliant 170 checkout before eighth seeds Ireland produced in the pressure moments, including O'Connor's 122 finish for a 3-1 lead, to seal an opening win.
Mansell said: "Three teams in a group and the priority's winning, how it happens or how you do it, it's just about winning. It was a priority to win today and give ourselves more breathing ground."
Two-time winners Wales also opened their account with a 4-1 triumph against Lithuania in their Group C clash.
Nick Kenny, who was making his debut alongside world No. 5 Jonny Clayton, said: "It was mint, and to do it with Jonny was even better.
"I thought I played alright, it was solid, but there's more to come from us, definitely."
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Hosts Germany began their campaign with a 4-0 demolition of the Philippines, while Hong Kong pulled off the major shock of the opening night with a 4-2 success against sixth seeds Belgium.
Japan came back from 2-0 down to edge a final-leg decider against Croatia, with Norway and the United States also winning by the same scoreline against Finland and Australia respectively.
Adam Gawlas hit three maximums as he guided Czechia to a 4-0 whitewash over India, Latvia and Sweden were both 4-2 winners against Italy and South Africa, while Poland eased to a 4-1 triumph over Portugal as did Austria against China.