South Africa's Branden Grace has withdrawn from the Barracuda Championship prior to the third round after testing positive for Covid-19, the PGA Tour said.

Grace, who was tied for second place after two rounds at Tahoe Mountain Club in California, must now self-isolate for 10 days, which will rule him out of next week's PGA Championship.

"I felt great all week," said Grace.

"Last night, I was tired and thought it had to do with the altitude. This morning, I notified the PGA Tour about my symptoms before going to the golf course.

"I wanted to get tested out of respect for my peers and everyone involved with the tournament.

"While it is unfortunate given my position on the leaderboard, the most important thing is our health."

The PGA Tour has implemented its response plan in consultation with medical experts, including working with those who may have had close contact with Grace.

Grace's caddie tested negative for the coronavirus but will quarantine for 14 days in line with the Tour's health and safety protocols.