MASON, Ohio -- It could be worse. If John Isner had known he was going to grow to be 6-9, "if a doctor or someone when I was 14 had told me I'd have been this tall," he said, "I probably can assure you I would have stuck with basketball."
That would have meant, going into next week's U.S. Open, that the top-ranked American male among the world's tennis pros would be no higher than No. 28, Sam Querrey. As it is, Isner's slip from No. 20 to 22 last week signaled the first time since the men's tour rankings were established in 1973 that no U.S. male was in the top 20.
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And an old anxiety over the state of American tennis has only worsened.
Andy Roddick, the last U.S. man to win a major title (the 2003 U.S. Open) and a constant presence among the top 10 for eight years, announced his retirement on his 30th birthday a year ago. Mardy Fish, a late-bloomer who spent most of 2011 in the top 10, is now 31 and hasn't been the same since a heart episode early last year. Barely active, he has plunged to 129th .
"I mean, we miss Andy, for sure," Fish said. "But I can't really speak too much on it. You know, I only look after myself, and I can't help that right now."
The Connors, McEnroes, Samprases and Agassis are long gone. The only active U.S. male singles player who has reached a major singles semifinal -- that was eight years ago, a loss to Agassi at the 2005 U.S. Open -- is 30-year-old Robby Ginepri (now No. 252).
Besides the 28-year-old Isner and Querrey, who is 25, the only other U.S. men in the top 100 are 20-year-old Jack Sock (87th) and 33-year-old James Blake (97th). And aside from the reality that tennis long ago became a truly global sport, the explanation for waning American tennis exceptionalism remains illusive.
"How many pages in your paper?" Ivan Lendl wanted to know when asked to address the situation. "You can discuss this forever."
The Czech-born Lendl, eight times a major tournament champion and now an American citizen living in Connecticut, these days coaches U.S. Open and Wimbledon champ Andy Murray -- the first British man to win a Grand Slam event in 77 years, from a nation that knows something about tennis droughts.
Ginepri wondered if common training camps for all top U.S. players would help. Murray theorized that Americans "are spoiled a little bit" by past dominance, and cited the long-held belief that other, higher-profile sports likely drain exceptional U.S. athletes from tennis, which tends to sit far higher in the athletic pecking order in Europe, Asia and South America.
There is a widely accepted theory that Americans, raised on hard courts, emphasize sheer power over the ability to construct points, while so many Europeans learn from a young age -- on slower clay surfaces -- how to probe for openings and manage aggressiveness.
The fact is that through the 1950s, '60s and early '70s, Australians won the majority of major men's titles. Yet, since 1976, only three from Down Under -- Pat Cash, Patrick Rafter and Lleyton Hewitt -- have won Grand Slam events.
"I don't know if you can teach a guy how to be a Grand Slam champion," said Brian Baker, the 28-year-old Tennessee native who joined the tour as the world's No. 2 junior player but, after a series of devastating injuries, is ranked 185th while attempting yet another comeback.
"I think you can coach a guy to make him really, really good," Baker said, "but he's probably got to have that extra special level to become a Grand Slam champion. It's pretty well documented that we don't have guys that are competing for Slams right now, and that's definitely a shock to American fans' systems."
Meanwhile, Americans' dropoff "doesn't mean anything to me," Isner said. "I haven't really put too much pressure on me to be the savior of American tennis or whatnot. I'm just trying to handle my business and play tennis as long as I can. I'm having fun doing it."