How did Tiger keep his secrets?

As the carefully constructed public image of Tiger Woods continued its excruciating free fall last week, one question perplexed those who think there should have been hints of trouble: How was it possible for Woods, among the world’s most scrutinized professional athletes, to keep his infidelity secret for so long?

Just about everyone is at a loss: the golf writers who banter with Woods (when he allows it), golf fanatics who can tell you which way his golf ball’s Nike logo was facing when Woods chipped it into the 16th hole in the final round of the 2005 Masters, paparazzi whose paid informants can sniff out a straying spouse a mile away.

How was Woods, 33, able to maintain a pristine image as a loving husband, father and son that was apparently at raging odds with his private life?

Some say Woods’ famously controlling nature allowed him to philander unsuspected. (On Friday he admitted publicly that he had cheated on his wife.) Some wonder whether intimidated golf reporters never pressed Woods because they did not want to risk losing the little access they had to the sport’s premier practitioner. Some believe that fellow players, had they suspected, would have kept mum because of Woods’ beneficial effect on TV ratings, their earnings and public interest in golf.

Others think the singular nature of professional golf itself made it possible for Woods to create a nearly impenetrable zone of privacy -- or secrecy.

“I wish I had some brilliant theory, because that’s been the big question to me,” said sportswriter John Feinstein, author of the bestselling 1995 book “A Good Walk Spoiled.” Woods is so reluctant to reveal personal information, said Feinstein, that the writer considered it a triumph when he coaxed out of Woods the relatively trivial fact that he was a registered independent. Still, Feinstein believes that Woods’ inner circle must have known he was straying.

“I can’t see how his agent or caddie could not have known,” said Feinstein. “It’s his agent’s job to know what the heck the guy was doing. If he didn’t know, he should be fired.” (Woods’ agent, Mark Steinberg, has only communicated with the media by e-mail and has never addressed whether he knew about his client’s transgressions.)

Not a team sport

Unlike other professional athletes, who travel with teammates, golfers can insulate themselves from prying eyes if they choose. Like other high-end golfers, Woods usually travels by private jet. When he takes a car anywhere, he usually drives himself. The lack of privacy common to team sports isn’t an issue.

“There are guys on the tour who have never met one another because they play at different times of the day,” said Feinstein. In 2007, he watched Nick Watney, who had just won his first PGA Tour tournament, gingerly approach Woods to introduce himself.

The night before the 2003 British Open, said Feinstein, Ben Curtis introduced himself to fellow pro Mike Weir. “So what brings you here?” Weir asked Curtis, who went on to win the tournament.

“The top players often stay in rented homes, and many even bring their own chefs to events, so there are fewer and fewer instances where, say, even at a major tournament, we’d run into them in town or at a restaurant as we once did,” said Jeff Babineau, editor of the Orlando-based Golfweek magazine. “Compare this to earlier eras when writers might dine or have a beer with Arnold Palmer or Jack Nicklaus on the eve of rounds at major tournaments.”

Babineau’s office is about 10 minutes from Woods’ home in Isleworth, a private golf community in Orlando where other sports stars and celebrities live. But even before Woods’ domestic troubles became known, he was rarely seen around town. “He’s left alone,” Babineau said.

‘Did I miss this?’

Doug Ferguson, an Associated Press reporter who has covered professional golf for 13 years, is among the few beat writers with whom Woods feels comfortable enough to chat. Ferguson never suspected the golfer was leading a secret life.

“You are thinking, ‘Did I miss this?’ But the truth is, I can’t think of a time I saw Tiger outside of a tournament, except a corporate thing he did in 2007 at Oakmont” -- a Pennsylvania country club -- “and a couple of his clinics,” said Ferguson. “I don’t know many people who saw him outside the golf course.”

Even the access that Ferguson has had to Woods, he said, never amounted to much in the way of news. “I keep reading that the press had to be nice to him or they would lose the interview, which is funny, because what interview? There was nothing to lose there. I have built up a comfort zone with him, but most of it was clubhouse, locker room, meaningless BS stuff.”

By arrangement with the PGA Tour, said Ferguson, Woods does not even enter the press room at a tournament unless he is a defending champion or close to the top of the leader board. “And it’s nutty,” said Ferguson. “The reason a lot of the press goes to tournaments is because Tiger is there.” Even when Woods does agree to answer questions, said Ferguson, he generally doesn’t offer much more than bland answers.

Until last summer, several people who write about golf said, they had not heard even a whisper of a rumor about Woods’ dalliances. But after the British Open in Turnberry, Scotland, where Woods did not play well, two British journalists called an American golf writer trolling for gossip about Woods’ marriage.

“If you’re kind of dialed in to what’s going on, you heard rumors over the summer about marital issues there,” said Daniel Wexler, a golf historian and author of several books. “But why would you pursue it? It’s not germane to what’s going on at the golf course.”

Woods has rarely been subjected to tabloid scrutiny in his professional career, which began when he dropped out of Stanford University to turn professional in 1996.

Early on, he learned a hard lesson about image-making when a profile in GQ magazine quoted him telling nasty jokes and using foul language. (“It’s no secret that I’m 21 years old and that I’m naive about the motives of certain ambitious writers,” Woods responded at the time. His father, Earl Woods, fretted during an interview with television journalist Charlie Rose that the piece might permanently damage his son.)

Brandy Navarre, owner of the Los Angeles-based paparazzi agency X17, said Woods was never on her radar as potential quarry. “I guess he put on such a good show we all thought there was nothing scandalous going on,” said Navarre.

Now an exclusive photograph of Woods could generate up to a million dollars in worldwide sales -- particularly if his face showed any bruises or cuts from his Nov. 27 car crash. “That’s definitely the money shot,” said Navarre.

Tabloid target

In the last two years, though, Woods has been in the sights of the National Enquirer, which in October 2007 broke the story of former North Carolina Sen. John Edwards’ affair.

Earlier that year, according to Neal Boulton, the former editor in chief of Men’s Fitness magazine, the National Enquirer squelched a story about a tryst Woods had in an SUV in exchange for Woods agreeing to pose for the cover of Men’s Fitness. Both publications are owned by American Media Inc. The New York Post reported the agreement Dec. 2.

“It took them several months to negotiate something that Tiger would agree to,” said Boulton, who quit his job before the Men’s Fitness cover story ran in August 2007.

Neither Barry Levine, the National Enquirer’s editor, nor David Pecker, chief executive of American Media, returned phone calls asking for comment, although Pecker told the New York Post that the story was untrue. Such deals, however, are not uncommon in the world of supermarket tabloids.

“One thing that rings true to me is that Tiger never does something for nothing,” said Feinstein. “He doesn’t say ‘I am going to pose for a cover ‘cause I am a good guy.’ ”

Last month, the National Enquirer set off the current furor when it published a story about “the New York City party girl who has been caught up in a cheating scandal with the multimillionaire golf superstar.” Since then, a parade of women has come forward claiming extramarital relationships with the golfer.

“It’s surprising none of the girls came forward earlier,” said Navarre, who is sending at least two photographers to Florida to cover the story for the foreseeable future.

On Friday, Woods announced he would leave professional golf for an indefinite period to work on healing his marriage. He asked his fans, colleagues and business partners for two things: understanding and privacy.