TROON, Scotland -- Citing health concerns -- but not specifically the Zika virus -- Jordan Spieth on Tuesday said it "was probably the hardest decision I've had to make in my life" when he decided to withdraw from the Olympic golf tournament.
For months, Spieth, 22, had professed his desire to represent the United States and participate in golf's return to the Games after 104 years. He had even been featured in advertisements for the Aug. 11-14 event in Brazil.
But like many of his peers, Spieth on Monday said he won't be making the trip and also said he would not defend his title at the John Deere Classic -- a PGA Tour event that is being played the same week.
"This was harder than trying to decide what university to go to," Spieth said Tuesday during a news conference at Royal Troon, where the 145th Open begins Thursday. "Whether to turn professional and leave school. This was something I very much struggled with. I bounced back and forth with, and ultimately a decision had to be made yesterday, and so I made it."
Why was it so hard?
"Because I'm a huge believer in Olympic golf," he said. "I'm a huge believer in playing for your country, showing I absolutely look forward to Summer and Winter Olympics. It's the most exciting sporting event for me to watch on TV, and to have a chance to be a part of it is something I definitely look forward to trying to do.
Spieth said that although he doesn't expect anyone to understand his decision, he believes it's the right one.
"Unfortunately, this is going to be a very, very difficult thing for me to do to watch the opening ceremonies and watch my peers compete for a gold medal or any medal for that [matter], and watch people stand on the stage and hear the national anthem playing."
Spieth said he's looked forward to Olympic golf since 2009, when its return to the Olympics was announced. He said he'll make it a "significant goal" to be at Tokyo in 2020.
Spieth would not specifically cite Zika as the reason for his withdrawal. He said reportssuggesting that he is doing so for just that reason are false. Rio has been plagued with health and security issues, and those factors undoubtedly weighed in his decision, although he would not discuss them specifically.
Ranked third in the world and basically the face of American golf after winning two major championships and the PGA Tour's FedEx Cup title in 2015, Spieth was viewed as an excellent ambassador for golf's re-entry into the Olympics.
But he joined the other top-four players in the world -- Jason Day, Dustin Johnson and Rory McIlroy -- in electing to stay home.
During a 30-minute news conference, Spieth fielded 22 questions, 13 of which were about the Olympics -- even though The Open is set to begin in two days.
"I can understand why people are skeptical," he said. "They're as passionate about the Olympics, as I am. They also are not in my shoes. So I feel that many, if not all of you, would have made the same decision I made if you were in my shoes. Whether you believe it or not, so be it. This is just something that was very, very challenging for me. I very much struggled with it. I certainly didn't want to have to do this during major week. Obviously, would have rather had the focus be on the Open Championship, but it hasn't been the beginning of this week. Hopefully it will after I leave this room."
Peter Dawson, the former head of the R&A and the current president of the International Golf Federation, on Monday said he thought the Zika threat had been "overblown," as few athletes from other sports have withdrawn because of it.
"It very well could be," Spieth said. "I'm not sure."
A year ago, Spieth won the John Deere Classic, then flew to St. Andrews attempting to make history by winning the first three majors in the same year. He came up one shot short of a playoff won by Zach Johnson.
This year, the Deere tournament was moved to the same week as the Olympics, but Spieth said he won't be defending his title.
"I don't think that's appropriate," he said. "I don't think it would be an appropriate move to play that week. So I will not be playing that week. I don't think it would be appropriate given our decision on the Olympics.
"But I do look forward to going back there. I love the tournament. I love the people. I obviously played it well."