Branden Grace withdrew from the Olympics on Friday, becoming the fourth golfer to cite the Zika virus as a reason not to play in Rio de Janeiro this summer.
At No. 11 in the world, Grace, a two-time winner this year, is the highest-ranked South African golfer.
"After serious consideration, it is with regret that I have decided to withdraw myself from the Olympic competition due to the risk posed by the Zika virus," Grace said in a statement. "Although it was a huge goal of mine to represent my country in the Olympics, we are getting married in November and hoping to start a family in the near future, so I must put the health of my family first."
Brazil has been the hardest hit of the approximately 60 countries that have reported an outbreak of Zika, the mosquito-borne virus linked to severe birth defects and possible neurological problems in adults.
The announcement comes two days after Rory McIlroy of Northern Ireland, the No. 4 player with worldwide appeal among golf's growing list of young stars, said he won't be part of golf's return to the Olympics because of Zika. McIlroy also is engaged and said he plans to start a family soon.