Branden Grace has become the latest golfer to pull out of the summer Olympics in Rio over fears around the Zika virus.
The 28-year-old South African cited his upcoming marriage and his desire to start a family as the main reasons.
"I am getting married in November and hoping to start a family. I must put their health first," he said.
"I really hope to be able to qualify again in four years' time."
Grace follows Northern Ireland duo Rory McIlroy and Graeme McDowell, who have already pulled out, as well as Fiji's Vijay Singh and Marc Leishman of Australia.
World No 1 Jason Day, meanwhile, says he is still considering his options.
Golf is returning to the Olympics for the first time since 1904.
Zika is a mosquito-borne virus which has been linked to brain defects in newborn babies.
The English Open has been revived as part of the new schedule.
Close House Golf Club, near Newcastle, will host the British Masters on July 22.
The event was last staged in 2002.
The tournament at Close House, scheduled to start on July 30, is set to be the first European Tour event since the coronavirus crisis halted action.
The world number one believes it would be the ‘right call’ to push the event back to 2021.
The exhibition match, against Phil Mickelson and Tom Brady, raised 20 million dollars.
The Dutchman finished third and second in the first two weeks of the home-based competition.
NFL stars Tom Brady and Peyton Manning will also be involved.
The US President was among the viewers watching the TaylorMade Driving Relief.
The US President phoned in as McIlroy played in a Sunday fundraiser for coronavirus victims.