TROON, Scotland (Reuters) - World number three Jordan Spieth has pulled out of next month's Olympics because of fears concerning the Zika virus, officials said at a news conference held at the British Open on Monday. Spieth's withdrawal means the Olympic golf tournament will be without the world's top four golfers. Jason Day, Dustin Johnson and Rory McIlroy had all previously said they would not be competing in the event. (editing by Rex Gowar)
