LOS ANGELES • Dustin Johnson has expressed his disappointment at having to withdraw from this week's CJ Cup in Las Vegas after he tested positive for Covid-19.

The world No. 1 underwent a test after experiencing symptoms of coronavirus ahead of today's opening round at Shadow Creek, the PGA Tour said in a statement.

The 36-year-old, whose last outing came at last month's US Open, is now in self-isolation, the tour added.

"Obviously, I am very disappointed," the American said.

"I was really looking forward to competing this week, but will do everything I can to return as quickly as possible.

"I have already had a few calls with the Tour's medical team and appreciate all the support and guidance they have given me."

Johnson's withdrawal comes after a stellar season in which he won three times and took home his first FedExCup championship at East Lake last month.

He was also named PGA Tour Player of the Year for the second time.

J.T. Poston will replace him in the CJ Cup field.

Since the tour restarted in June after a three-month shutdown caused by the pandemic, PGA Tour events have been taking place without spectators while players are not allowed to enter "the bubble" for each tournament without recording a negative test first.

Johnson is the most high-profile golfer to test positive for the virus since the 2019-2020 season resumed, while Briton Sam Horsfield and American Scottie Scheffler were unable to compete at the US Open due to their positive Covid-19 tests.

The news comes one week after American Tony Finau was forced to withdraw from the Shriners Hospitals for Children Open after testing positive for the virus which has killed more than 215,000 people in the United States.

Finau will not compete at the CJ Cup either. This year's event has been moved from South Korea's Jeju Island to Las Vegas due to the pandemic.

AGENCE FRANCE-PRESSE, REUTERS