Padraig Harrington has withdrawn from the AT&T Pebble Beach Pro-Am after testing positive for Covid-19.
The Ryder Cup captain took part in the Phoenix Open last week and had been poised to compete in his fourth PGA Tour event of the season in California.
Harrington will now undergo a period of self-isolation under American CDC guidelines.
Korean golfer Bae Sang-moon will take his place at the Pebble Beach event, which will take place at two courses.
The tournament has had to make changes because of the pandemic, with the Pro-Am portion cancelled because of Covid-19 protocols.
Instead of being contested across three courses this year, the event will take place at Pebble Beach and Spyglass Hill, with the cut falling after 36 holes instead of 54.
World number one Dustin Johnson, fresh off his triumph at the European Tour's Saudi International, has also withdrawn from the event.
Johnson, whose latest win marked his ninth European Tour title, felt it would be best to enjoy a week at home before competing at the Genesis Invitational and the World Golf Championships at The Concession.