Ranked No. 1 in the world and carrying streaks of four grand slam championship and with 30 consecutive major-tournament match victories, the notion of Novak Djokovic losing at Wimbledon to an American — any American, unless maybe John McEnroe came out of the announcer’s booth — seemed ridiculous.

But there was Sam Querrey yesterday, celebrating after Djokovic hit wide to end a match delayed by darkness and rain, spread over two days, with the world’s 41st-ranked player defeating its No. 1 by a score of 7-6, 6-1, 3-6, 7-6.

During most of the history of tennis, Americans ranked among the elite in men’s tennis — but that ended more than a decade ago, and Querrey’s third-round win has to be the greatest result by a Yank in a major since Andy Roddick won the U.S. Open in 2003 — the most recent grand-slam championship by an American man.

Querrey’s shocking triumph, however, almost certainly does not presage a new era of outstanding U.S. players.

If anything, it simply points up how far the American men’s game has fallen since the days of Pete Sampras and Andre Agassi and Jim Courier and Jimmy Connors and McEnroe …

When I was young, Americans were always contesting major championships in tennis. Going back to Stan Smith, Arthur Ashe, Jack Kramer, Don Budge and Bill Tilden, the latter at his peak nearly a century ago.

The U.S. had the tennis craze of the 1970s (ask your grandparents about it), and it looked like the game would be an American pursuit forever.

But even as McEnroe, Agassi and Sampras carried U.S. might to the end of the last century, the game was being hollowed out, at home.

People who have spent far more time thinking about this than I have seem uncertain What Happened.

Tennis lost its social cachet in the U.S. about the time that disco died, and no major presence has made himself known since Roddick, who began his rise in 2000, reached No. 1 briefly in 2003, but has been retired for four years.

Meantime, tennis has become a sport sometimes watched by Americans but rarely/never featuring an American man in the latter stages of a major tournament. It costs a lot of money to be good at it, and nobody seems interested in the effort. Tennis is just not that popular, in the U.S. It certainly is no longer a participant sport of any significance. That would be soccer.

The highest-ranked American, still, is Jon Isner, who is 6-foot-10 and has a killer serve, but whose mobility is limited. He has one quarterfinal appearance in a grand slam, and a complete explanation of his game can be found in one remarkable score: A 6-4, 3-6, 6-7, 7-6, 70-68 victory over Nicolas Mahut at Wimbledon in 2010 — the longest match in pro tennis history.

Isner’s serve was too good to be broken; his all-round game was too limited for him to break.

Querrey is rather like a slightly shorter Isner (6-foot-6), again known for a big serve but also someone who is unlikely to be hanging around in the latter rounds of a significant tournament.

American tennis keeps waiting for the next male star, but none are in sight. Still.

Isner remains the U.S. No. 1, at No. 17 in the world. Jack Sock (you are forgiven for not knowing him) is No. 26. Steve Johnson is No. 29. And that’s it for Americans in the top 40.

Querrey, 28, is No. 41, and he seemed to enjoy his day in the sun, after defeating Djokovic. He revealed (to most of us) that he perhaps is not quite as hungry and concentrated as he should be, but he’s working on it. “Hunger” may be an issue among the current generation of men’s players.

Querrey had a two-set lead when play was halted on Friday, and had most Saturday to think about how he might lose it against Djokovic, but he said slept like a baby and wasn’t nervous and he hung on. He said he hopes the result might get him going again — back towards his best ranking of 17th, in 2011.

Good luck with that, Sam.

To overcome the negative momentum of American men’s tennis would require something like renewed interest and enthusiasm from the U.S. upper-middle class, which can afford personalized coaching … or some transcendent talent coming out of nowhere.

As for the American women … as long as the Williams sisters are playing, things look good. But it may be just be as grim among the women soon as it is among the men, where beating someone good represents a very good day.