Branden Grace withdrew prior to Saturday's third round of the Barracuda Championship after testing positive for COVID-19.
The 32-year-old South African was tied for second place through two rounds at the PGA Tour event at the Tahoe Mountain Club in Truckee, Calif.
"Last night, I was tired and thought it had to do with the altitude," Grace said in a statement. "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."
Grace must now self-isolate for 10 days, which knocks him out of next week's PGA Championship in San Francisco.
He is the eighth PGA Tour player to test positive for the coronavirus since the tour resumed play in June.
The tour said Grace's caddie tested negative but will follow protocol and enter a 14-day quarantine period. Additional contact tracing didn't produce any positive tests.
Grace has won nine titles on the European Tour and one on the PGA Tour, the 2016 RBC Heritage. He missed the cut at his previous four PGA Tour events heading into the Barracuda Championship.
--Field Level Media