It began with a fighting comeback by Madison Keys, wherein she edged Anna Bondár by a few points in a deciding 10-point tiebreak, used in the third (fifth for men): you take turns serving twice, first to 10 with a two-point spread. (RELATED: Madison Keys’ U.S. Open Collapse Offers a Lesson in Winning and Losing)

Then Qinwen Zheng came back in the second set against Miss Keys and edged her in a regular seven-point second-set tiebreak, and made a second comeback in the third and roared past to 7-5 and match.

After which Miss Zheng came back from 0-5 in the first set against multiple major (Slam) winner Iga Świątek (Qinwen has Olympic gold) and took the match.

In the quarterfinals, the tall, lithe star from Shiyan (northern China) played a steadier, stronger first set against No. 2 seed Elena Rybakina, 6-3, but the Moscow-born Kazakh second seed made an ice-cold comeback in the second, 6-1, and coasted to the win in the third.

American favorite Coco Gauff, with a 0-5 record against Russian teen phenom Mirra Andreeva, was intimidated in the first set but found her groove in the second. Turning the tables, she won a close tiebreak in the second, went on to her own intimidation in the third, getting her opponent thoroughly out of sorts and off her game.

Coco Gauff goes up against Elena Rybakina for a place in the finals, meeting either the other American favorite, Jessica Pegula, or Belarusian glamor girl and repeat defending champion Aryna Sabalenka. Miss Sabalenka did not require any comeback heroics en route to this grand moment. Miss Pegula, from Buffalo, N.Y., and an ardent fan of the NFL Bills, is the only one of these four, who are the top four seeds, to not have a major on her resume, but she is currently the top-ranked American.

And that is only the women’s draw.

In the men’s draw there has been plenty of come-from-behind drama as well. The top seed, Germany’s Alexander Zverev, who won his first major a few months ago at the French Open, is in the semis against veteran hard-hitting Russian Karen Khachanov, unseeded but regularly able to make deep runs, who showed his grit in tough five- and four-set matches against medium seed Californian Learner Tien and high-seed Canadian Felix Auger-Aliassime.

The men’s draw has been more wide-open than usual because the mighty Novak Djokovic, last of the Big Four tennis titans of the early 21st Century, exited in a five-set first-round loss in which he was visibly ill, and of course Rafael Nadal and Andy Murray have been out for a couple years and Roger Federer, the legendary five-in-a-row champion here, a few years longer. He was inducted into the Hall of Fame at Newport, RI, just before the tournament began; there was a moving speech by his beloved better half, Mirka, who said she loved him more as friend and husband and father and son to his parents (who were present and tearful) than as a great champion, and he was feted on one of the evening sessions in a way only a big New York event can fete.

And Stan Wawrinka and Gael Monfils, legendary players very much loved in New York, played their last matches. And so yes, there was a change of the guard, and it shows in the way the trophy is up for grabs. If Zverev beats Khachanov — no sure thing! — he will meet in the final one of two Americans, Georgia’s (and Florida’s) Ben Shelton and Maryland’s Frances Tiafoe, both of whom played fantastic quarter-finals.

Indeed, Shelton’s semi-final slot, earned against defending champion Carlos Alcaraz, back from a long layoff due to a wrist injury, went five sets, and there’s no need to count how many times you hear people say this was the most amazing match ever played in Arthur Ashe Stadium. Of course it was not; no match is, but it was that kind of match.

Nearly five and a half hours, the longest ever, ending at what will become an iconic hour in sports history, 3:33 in the morning, come-back, fall-back, come-back again, every imaginable unbelievable shot, a 146 ace to finally put an end to it — in a ten-point tiebreak, what else? — you could not ask for more.

And Tiafoe — as if it needed saying — came from behind zero sets to two to out-hit and out-play his friend Alex Michelson, he too, of course, in a ten-point tiebreak.

Only in New York. Only in tennis. Say what you will about this sport, it has all the thrills of soaring and collapsing emotions, all the beauty of acrobatic, even balletic, athleticism and all the drama of the joyous triumphs and wrenching heartbreaks. It is something worth keeping in these chaotic times.

READ MORE from Roger Kaplan:

Madison Keys’ U.S. Open Collapse Offers a Lesson in Winning and Losing

Gritty Play on Court 17: Dane Sweeny Stuns Lorenzo Musetti at US Open

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