Coaches and pundits can make tennis seem pretty complicated, but Isner figured out something when he was at Georgia. He realized that, for him at least, getting good was all about playing matches. Matches, matches and more matches. "I think college tennis makes you tough," he says, trying to explain the roots of his outstanding match temperament. "I was playing 60, 70 matches a year in college. In the pros, unless you’re winning, you’re not playing that many. If you’re too young, you’re just banging your head against the wall. You don’t build confidence that way.

"In college, you’re in situations where the whole [team] match is riding on you, the team is depending on you. You have to be strong. You have to be tough. I’ve got a pretty good record in close matches. I don’t exactly know why that is, maybe just a different level I’m able to find in the nitty-gritty of a match."

Isner’s coach since early 2009, Craig Boynton of the Saddlebrook Resort, has a different explanation. "John is a big-match guy. When the spotlight is hot, he’s going to be good. He’s about the worst practice player you can imagine. If he played on the ladder with the teaching pros at Saddlebrook, he’d probably end up at the bottom."

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Pat McEnroe, the U.S. Davis Cup captain, has a similar opinion. Playing singles for the U.S. for the first time last March, in Belgrade, Serbia, Isner lost a close four-setter to Viktor Troicki to start the tie. The next day he was named to replace an ill Mike Bryan and helped Mike’s brother, Bob, secure the tie-saving doubles. Isner then lost to heavily favored world No. 3 Novak Djokovic in five sets. "I could almost see John change from a nervous rookie to a seasoned, strong competitor over just three days," McEnroe says. "I love this kid’s attitude and match temperament."

The world got to know that temperament very well over the course of 11 hours, 5 minutes at this year’s Wimbledon. That’s the time it took Isner to become a household name when he beat Nicolas Mahut in the first round, 70-68 in the fifth set, in the longest match ever played. In the process, Isner hit 112 aces, shattering the old record by 34.

The win made Isner famous, but it also validated his improved work ethic. He had endured a frustrating slump through most of 2008 and admits to perhaps a grain of truth in those rumors that he wasn’t working hard enough. "I don’t really think that [laziness] was the main factor," he says. "I think I just got way out in front on my learning curve. I never really graduated from that Challenger level. Since the beginning of 2009, I’ve worked extremely hard."

The world may have been amazed by Isner’s win at Wimbledon, but others are amazed that he’s on the tour at all. He is, after all, the kind of player who wasn’t supposed to happen. But here he is, hitting it big at 25, with low mileage on his ATP odometer.

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