SUTTON KNOWS HE has enemies. Athletes invited to join his squad, team TBB, are warned that he's "damaged goods."

"I get the rejects, the ones who are desperate," he says melodramatically. "Others won't come near me because I'm tainted."

Obviously, athletes like Wellington have accepted who he is. "All I could do is go by what I saw and the relationship I established with him in a short amount of time," she told me in the Philippines. "I saw nothing that gave me any concern, and still haven't." What they get in return is a level of expertise that will take some of them to the top. For this reason, Sutton has no shortage of applicants, and he tends to turn people down at least twice before agreeing to coach them. He almost always says no to Americans, whom he considers "soft."

The morning after my first talk with Sutton, he gives me a ride in his minivan to a 7 a.m. swim session at a community swimming pool. Twelve sleepy-looking triathletes are sitting under a palm tree, eagerly waiting for the gate to be opened—among them Wellington and Reto Hug, a two-time Olympian from Switzerland. Some of the athletes are away from the camp right now, but the full squad numbers only 18. Sutton prefers not to work with too many people at once, a rarity in the age of Web coaching. "I know I could have 100 people here and make more money," he says. "But that's not what I'm about. Coaching is sacred to me."

During the 90-minute session, they will swim three miles' worth of intervals, the first of the day's three workouts. In the hours ahead, I'll see a few glimpses of Sutton's hard-man side. One of the triathletes has a water bottle on deck and starts sipping from it between swimming sets. Sutton sees it and hurls it over a fence. "I haven't yet seen an aid station at an Ironman swim," he shouts. "If you win a world championship, then you can bring a drink."

The Bobby Knight moments are few, however, and what stands out more is Sutton's ability to see into the depths of an individual. He examines each athlete and issues unique instructions one-on-one, as if he were coming up with plans on the spot. Greg Bennett, whom Sutton turned from an average pro to a star in the late nineties, told me about the Sutton eye.

"He has learned how to read animals that are fatigued," he said, "so when he's taking on people, isn't that just another animal?" Bennett added that this skill helps Sutton push his athletes to the brink but not over it. "There were weeks and months where I pushed myself harder and longer than I ever could have imagined. You go into a workout thinking, There is no way I can do what he's after, and yet day in and day out your body responds."

In the pool that morning, Wellington does her swim with Bella Comerford, a 31-year-old Scot. Wellington and Comerford demonstrate the contrasting types that Sutton looks for in athletes: They have different levels of natural ability, but they both have a killer work ethic. Wellington, who came to Sutton after competing at the amateur level for three years, was the type of raw talent that other coaches might have overlooked. But she has incredible genetic gifts—Sutton calls her a "thoroughbred"—so she needs only a few months of training to achieve good form.

Comerford, in contrast, wins by virtue of hard work. "A plow horse," Sutton calls her. Even if she never wins at Hawaii, in the series races that are triathlon's bread-and-butter, she's a star. In the first half of 2008, she won Ironman South Africa and Ironman Lanzarote, the latter contested on what's considered the toughest course in the sport.

"We call her the little Nazi," Sutton says. "Bella is my champion soldier."