Last October, I watched a former environmentalist from Suffolk, England—Chrissie Wellington, a cheerful woman whose friends call her Muppet—win the Hawaii Ironman. None of the experts on the Kona course had ever heard of her, and when she took the lead after the halfway point, we assumed she would blow up. Upstarts aren't supposed to have a prayer in Hawaii, but Wellington owned the race, finishing the 2.4 miles of ocean swimming, 112 miles of biking, and 26.2 miles of running in 9:08:45, five minutes ahead of the next-fastest woman, Samantha McGlone.

At a press conference that evening, we learned that Wellington had quietly raced and won her first Ironman, Ironman Korea, seven weeks before Hawaii, a decent feat but nothing compared with a victory at the Ironman world championship. Equally mystifying was the fact that she'd been a pro, training seriously, for only nine months.

At one point during all this, Wellington took a moment to thank her coach, who wasn't there but whose name was very familiar to people in the know: Brett Sutton. And with that, the reaction to her win shifted from "How did this happen?" to "Oh." Since then, she's proved it was no fluke. Earlier this year she won Ironman Australia and Ironman Germany. Returning to Kona on October 11, she's a favorite to defend her title in triathlon's greatest event.