After that year's U.S. Open, McEnroe would never win another Grand Slam or be ranked No. 1 again. It was as if the near-perfection of 1984 hadn't fulfilled him. More often than not, he seemed disgusted on the court. Brad Gilbert, now Andre Agassi's coach, describes an uproarious 1986 McEnroe meltdown in his book "Winning Ugly: Mental Warfare in Tennis." Gilbert was the mirror image of McEnroe, a player short on natural talent but long on workmanlike desire. "Gilbert, you don't deserve to be on the same court with me!" McEnroe snarled at his opponent during a changeover when it became apparent he might lose to him. "You are the worst! The fucking worst!" After the loss, McEnroe announced he was going on what turned out to be a seven-month sabbatical, because "when I start losing to players like him, I've got to start reconsidering what I'm doing even playing this game."

By then, the game of tennis was changing. Pure power players like Boris Becker, with his 125-mph serves, were ascendant, aided by new racket technology that increased power without sacrificing control. Though still one of the top two or three players in the world, McEnroe, with his artistic flair for finesse volleys and quirky angles, was suddenly a stylistic anomaly. In addition, for the first time in his life, tennis wasn't monopolizing all of his intensity. In 1984, McEnroe met his temperamental equal in O'Neal and the two wed in 1986 (the press dubbed them "Tantrum and McBrat") after he'd called her "the female John McEnroe." Indeed, she'd barred her father, the hot-tempered actor Ryan O'Neal, from the wedding when it was rumored that he'd called McEnroe "a jerk." After six years of marriage, five homes (including a Malibu beach house purchased from Johnny Carson for $1 million and three tennis lessons) and three children, O'Neal and McEnroe parted ways, ostensibly because she wanted to work and McEnroe wanted her home with the kids. "I've had a lot of experience with men who are bullies," O'Neal told Entertainment Weekly. "Taking on John McEnroe was the biggest struggle of my life."

In 1992, while his marriage was crumbling, McEnroe reached the semifinals of the U.S. Open and led the United States to a rousing Davis Cup win over Switzerland. While other top American players, ranging from Connors to Pete Sampras, haven't always made the Davis Cup a priority, McEnroe led the Americans to five world titles in 12 years. Fittingly, the last great moment of his tennis career came during the '92 Cup, when he played doubles with rising star Sampras. When the Americans won, McEnroe unfurled a giant American flag and ran laps around the court, waving it and screaming, the normally placid Sampras in lockstep.

Though he didn't officially retire, his tennis waned while McEnroe tried to find other outlets for his creative impulses. McEnroe had visited his first art museum in 1977, when his mixed-doubles partner and childhood friend, Mary Carillo, took him to a Claude Monet exhibit in Paris during the French Open. "I remember him standing in front of one of the great Monets and saying, 'You gotta be kidding, my brother Patrick has better stuff than this on the front of our refrigerator!'" Carillo told the Guardian in 1994. "But I guess he's coming around. He always did like to hang around eccentric, creative people."

Later, the late Vitas Gerulaitis, a fellow pro and New Yorker, started ushering him around SoHo galleries. He bought his first painting, by the realist Audrey Flack, at a gallery on Prince Street and began visiting museums and galleries nationwide while on the tennis circuit. In 1993, while separated from O'Neal, he apprenticed at a gallery on East 79th Street, spending all day looking at art. "I was really down and out at the time," McEnroe told the Independent in 1994. "I had just been separated and it was a godsend to be able to go to a place every day and keep my mind off what was going on. Because of that, I became more interested in the idea of doing something on my own."

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