(Reuters) - World number one Dustin Johnson has pulled out of this week’s CJ Cup after testing positive for COVID-19, the PGA Tour said in a statement on Tuesday. The 36-year-old American, who last competed at September’s U.S. Open, notified Tour officials he was experiencing symptoms and was administered a test, leading to his withdrawal from the Las Vegas event as he begins to self-isolate, the Tour said. “Obviously, I am very disappointed,” Johnson 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 has had a sensational year, winning three times and taking 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 Johnson in the CJ Cup field. 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. A handful of professional golfers have tested positive for the novel coronavirus since the PGA Tour returned in June, including Briton Sam Horsfield and American Scottie Scheffler, who were unable to compete at the U.S. Open due to positive COVID-19 tests.