TORONTO — Warm sunshine pierced the overcast sky during the first round of the RBC Canadian Open, even as the PGA Tour event was overshadowed by other news in the world of golf.

Wyndham Clark held on to his clubhouse lead to finish the first round of the Canadian Open atop the leaderboard. No one in Thursday afternoon's wave came close to the American's bogey-free 7-under 63.

"I haven't shot a low one in a while," said Clark. "I've had a couple under par, 3, 4-under pars in my last few events, but really felt like I left a lot of shots out there.

"This round I maximized pretty much everything out there."

Matt Fitzpatrick sat second, a shot behind Clark, at the 111th edition of Canada's national men's golf championship. Doug Ghim and Harold Varner III were tied for third at 5 under. Varner was the only player in the afternoon to crack the top three.

Cloudbursts in the morning and the afternoon kept the course at St. George's Golf and Country Club soft. A strong wind helped keep the temperature down, but sent some drives into the long rough.

"I knew you had to hit the fairway, and that's all I really focused on," said Varner. "It got pretty windy out there, just hard to get it where you need to be to score."

Mackenzie Hughes of Dundas, Ont., was the low Canadian. He was tied for fifth at 4 under with Tony Finau, Lee Hodges and defending champion Rory McIlroy.

"Any tournament, you're kind of working yourself into it on Thursday," said Hughes. "You can't win on Thursday, but you can play your way out of it."

Even as players and fans celebrated the return of the Canadian Open — it was cancelled the past two years due to the COVID-19 pandemic — controversy dogged the event as it went head-to-head with a new rival.

The LIV Golf Invitational, which hopes to supplant the PGA Tour as the top men's golf circuit in the world, is hosting its first event this week at the Centurion Club outside London, England. The Saudi-backed league is offering large sums of guaranteed money to some of the highest profile players in the sport.

Dustin Johnson, the 2018 Canadian Open champion, is the biggest name to defect so far. He resigned his PGA Tour membership on Tuesday.

PGA Tour commissioner Jay Monahan announced Thursday morning that anyone who jumps ship to the upstart league will no longer be eligible for PGA Tour events. The ban includes participation in the Presidents Cup, for which the International team is determined by the world ranking.

Monahan said in a memo to tour members that even if players resigned ahead of the first LIV event outside London, England, they will not be allowed to play PGA Tour events as a non-member by getting a sponsor exemption.

"I'm pleased. I think anybody that's shocked clearly hasn't been listening to the message that Jay and everybody's been putting out," said world No. 6 Justin Thomas at St. George's after shooting a 1-under 69. "They took that risk going into it, whether they thought it was a risk or not."

McIlroy said he would watch what he could of the LIV event on YouTube — CHCH TV in Hamilton is the only channel in Canada showing the tournament but its coverage will begin with Saturday's final round — but he agreed with Monahan's decision to punish the defectors.

"I think that the majority of the membership that are here this week and that haven't went and played elsewhere really appreciate that," said McIlroy. "So I think (Monahan's) done the right thing because these guys have broken rules and done things outside of the tournament regulations."

This report by The Canadian Press was first published June 9, 2022.