Australian golfer Marc Leishman has pulled out of the Olympic Games in Rio over concerns about the Zika virus.
The mosquito-borne virus, centred in north-east Brazil, has been declared a global public health emergency as it spreads through South America.
It is being linked with thousands of babies being born with underdeveloped brains.
Leishman said he was concerned about the risks of transmitting the virus to his wife, who has a poor immune system.
The world number 35 said he "almost lost" his wife, Audrey, to toxic shock syndrome last year and that she was still recovering.
"It was a difficult yet easy decision not to participate," said Leishman, 32, who would have represented Australia in Rio this summer.
"We understand that family must always come first and we respect Marc's decision not to play in Rio," the Australian team chef de mission Kitty Chiller said.
Golf is returning to the Games after a 112-year absence, with the world's biggest names such as Jordan Spieth, Rory McIlroy and Jason Day.
Tournament entrants will be finalised on July 11 based on world rankings.
Leishman's compatriot and former Masters champion Adam Scott will not play, saying he wanted to focus on the PGA Tour.
South Africans Louis Oosthuizen and Charl Schwartzel will also be absent, as will Fijian triple major-winner Vijay Singh.