Jaco van Zyl has questioned the motives of the plethora of star golfers who have withdrawn from the Rio Olympics.

Rory McIlroy, Jordan Spieth, Jason Day and Dustin Johnson have all pulled out of the tournament in Brazil, with the Zika virus - which has been linked to severe birth defects - the predominant reason cited for doing so.

But South Africa's Van Zyl, who himself is only playing due to the withdrawals of countrymen Louis Oosthuizen, Branden Grace and Charl Schwartzel, believes Zika has been used as a "convenient" excuse for not travelling to Rio.

"Honestly, I can't feel that the Zika virus would be their reason not to go, the Zika virus is in Florida," Van Zyl said.

"I think they have got other reasons for not wanting to participate and the Zika virus is a very convenient way for them to get out of it."

While many of golf's stars have shunned the chance to play at the Olympics, for Van Zyl winning a gold medal would represent the pinnacle of his career.

"If I can choose one [a major championship win or an Olympic gold medal] I would definitely take the gold," he added.

"The reason being that there are four majors every year and one Olympic gold medallist in 112 years. To get an opportunity and let it pass by doesn't make much sense to me.

"I personally feel every opportunity you get to represent your country is a great privilege."