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In seven weeks, golf will return to the Summer Olympics for the first time in 112 years. It is getting increasingly difficult to tell how many of the world’s top players will be there.

For months, as questions persisted over whether PGA Tour pros were sufficiently jazzed about the event, organizers emphasized that stars such as Jordan Spieth and Jason Day were enthusiastic. But enthusiastic and committed are proving to be two very different things.

Just a few weeks after declaring himself “ready to play,” world No. 4 Rory McIlroy released a statement Wednesday saying that he has decided not to travel to Rio de Janeiro for the Olympics, citing concerns over the Zika virus.

“Even though the risk of infection from the Zika virus is considered low, it is a risk nonetheless and a risk I am unwilling to take,” said McIlroy, who was born in Northern Ireland but planned to represent Ireland.

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Hours later, top-ranked Jason Day of Australia said he couldn’t yet commit to the men’s tournament, which begins Aug. 11.

“It’s a life decision that you have to make,” Day said during a visit to Baltusrol Golf Club, where he will defend his PGA Championship title next month. “Family for me is priority number one. I have to make sure that they’re happy, and from there I’ll make the decision.”

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