Rahm initially tested positive in early June and had to withdraw from the Memorial Tournament where he held a six-shot lead after 54 holes, before bouncing back to win his first major title at the U.S. Open 15 days later.

The 26-year-old Spaniard was then subject to strict coronavirus protocols at both the Scottish Open and The Open Championship, but tested positive after returning to the United States before his planned flight to Tokyo.

Rahm was still at a loss as to how it happened as he prepared for the first leg of the lucrative FedExCup play-offs, The Northern Trust, starting at Liberty National on Thursday.

"It really is unfortunate. It sucked because I wanted to represent Spain." - Jon Rahm.

"This was a little harder to digest than Memorial because I've done everything the system tells me to do," Rahm said of his second positive test.

"First one on Thursday negative, Friday negative, Saturday I get my first positive. And then they tested me again that same day, and I apparently was positive again.

"So I can't really explain what in the world happened."

Rahm hoped to bounce back at the 125-strong FedExCup playoff opener.

"It really is unfortunate. It sucked because I wanted to represent Spain (at Tokyo)," he said of his Olympic withdrawal.

"I wanted to hopefully give Spain a medal. I was wishing for a gold medal, but just being part of that medal count for the country would have been huge.

"It was more devastating in that sense. I was more in the mindset of playing for them more than me.

"Still makes me a little sad, I'm not going to lie. I'm going to have to wait three more years hopefully to qualify for the Olympics, but I was really ready for this one."

Asked if he had symptoms following his most recent positive test, Rahm added: "Well, I wasn't ill. I can guarantee you I didn't have COVID this time, not at all.

"I had five tests done, four of them were negative, one was positive. "That first time I did have COVID, barely any symptoms, but I had it. This time I had nothing."