PARIS (AFP) - Rory McIlroy defended on Wednesday the growing number of top-ranked golfers pulling out of the Rio Olympics and denied it represents a stinging embarrassment to the sport.

Golf is returning to the Olympics for the first time since 1904 in August but will not feature world number one Jason Day, fourth-ranked McIlroy or US Open runner-up Shane Lowry because of fears over the Zika virus, to name just a few big names.

"As a tool to grow the game around the world, I think it's great," McIlroy, a four-time major winner, told reporters ahead of the 100th French Open, of golf's inclusion at the Olympics.

"Some people argue it would have been better to send amateurs there, but the whole reason that golf is in the Olympics is because they want the best players to go and compete.

"Unfortunately with where it is this year, people just aren't comfortable going down there and putting themselves or their family at risk.

"I'd say if the Olympics were in most other cities or most other countries in the world you wouldn't have as many people not wanting to go and participate."

Day and Lowry on Tuesday joined the likes of McIlroy, Graeme McDowell - both down to compete for Ireland - Fiji's Vijay Singh, Marc Leishman of Australia and South Africa's Branden Grace in announcing their intentions not to compete at the Games starting on Aug 5.

Disease experts say that only pregnant women and people planning a family need fear Zika, a mosquito-borne virus which can also be transmitted via sex and is thought to cause a form of severe brain damage in babies.