Former world number one Greg Norman is in hospital in the United States with coronavirus symptoms.
The 65-year-old Australian tested negative on Tuesday but said on Thursday he had a mild fever, cough, aches and pains and a headache.
The 1986 and 1993 Open champion then posted a picture of himself on social media from his Florida hospital bed.
"This sums it all up. My Christmas Day," he said, adding that he wanted to "get this [virus] behind us".
Norman spent more than 300 weeks at the top of the world rankings and was inducted into the World Golf Hall of Fame in 2001.
He competed in last week's PNC Championship in Orlando with his son, Greg Jr, finishing in a share of ninth.
His son confirmed that he and his wife had tested positive for Covid-19 and were isolating at home.
England's Ian Poulter was among those who sent messages to Norman, wishing him a "speedy recovery".
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