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Our greatest sporting events give us wild shifts in momentum. We are fascinated when virtually unknown athletes – fresh and fearless – rise to defy icons. And we relish high drama on our greatest stages at just the right time.

Twenty-five years after the aging American legend Jimmy Connors thrilled the world in Flushing Meadows, a young, little-known French outsider with dreamy blue eyes, an endearing accent, wavy hair and a pink hat stepped out onto Arthur Ashe Stadium and shocked 23,000 US Open fans and millions beyond with his 6-1, 2-6, 6-4, 3-6, 7-6(6) win over one of the most beloved players in the Roger Federer-less draw.

Never mind that Lucas Pouille is the definition of obscure, that he is a Frenchman who was born in the outer provinces and now calls Dubai home. Never mind that he had played two straight marathon matches, that he had been crushed in Monte Carlo the last time he played Nadal, that Rafa again blasted him off the court when they practiced just before the Open, that he has never won an ATP title, is “only” ranked No. 22, and over his career he has a losing record.

The humble, handsome, soft-spoken hunk is hardly a loser. Plus the kid likes to do things differently.

Before Wimbledon he hadn’t ever won a match on grass. But he beat Bernie Tomic and Juan Martin del Potro en route to the quarterfinals. And today, he not only unleashed a torrent of nasty groundies, he seemed some possessed with a curious, almost inexplicable sense of destiny. Maybe the Gallic guy was channeling the beaming spirit of Yannick Noah – the last Frenchman to win a Slam – who conveniently was in the stands today with a Knicks cap. Or maybe he just relished the moment and the opportunity to step up against the great Rafa on the biggest stage in the sport.

In any case, tennis was treated to a Labor Day weekend match for the ages, a battle filled with delicious drop shots, spectacular retrievals of overheads, twisting backhand overheads that astounded, a forehand error that shocked, superb athleticism and more swings of momentum than a pendulum on steroids.

If nothing else the fourth-round classic was a case study in the changing fortunes in tennis – some massive, some a matter of degree. It was apparent from the very first points that Rafa was in for a battle, as Pouille came out swinging, blasting backhand winners at will to take the first three games and eventually the first set 6-1. The crowd was stunned. Yes, Nadal can point to 14 Slam trophies in his own personal museum in Mallorca. Still, “Rafanatics” around the world were sweating. Their man, who had made just two quarterfinals in his last nine Slam appearances, was again in a world of bother.

But the Spanish counterpuncher quickly became more aggressive, seizing a 3-0 lead and storming the net at key moments to take the second 6-2. In the hour-long third set, Pouille grabbed an early break, then held firm throughout, closing things off at 6-4 with a service game that opened with a pair of aces. Next, in the topsy-turvy fourth set, the players traded three breaks in a row mid-set before Rafa closed it out at 6-3.

At the outset of the decisive fifth, Rafa broke Pouille then held to go up 2-0. Millions around the tennis world sighed. Now, all the great man had to do was hold his remaining service games to take the match. No problemo, si? For a while Rafa was holding serve more easily than Pouille. But at 4-3, 30-0, Pouille’s forehand began to catch fire again, and Rafa received a time violation warning and misfired some groundies. Suddenly they were back even at 4-4, with the French fellow having the advantage of serving first.

At 4-4 Rafa forced a break point with a mind-boggling defensive save from a Pouille overhead. The stadium erupted. Surely this would be the telltale moment of the match. But no, the kid somehow steeled himself and blasted more forehand winners to hold. This your-turn, my-turn back and forth couldn’t go on forever. A tiebreak approached. Rafa held more easily, with Pouille being taken to deuce on his final service game.

Yet even the tiebreak swung back and forth, dare we say, like a snooty Parisian’s taste in ladies. Pouille took an early lead, reaching 4-1 with an ace. Nadal’s goose seemed sauteed. Then Rafa crept back to 4-3. A massive down the-line-backhand by Rafa went a few inches wide – then Pouille hit another forehand winner to go up 6-3. Certainly Rafa couldn’t even things. Yet he saved three match points as Pouille netted forehands. Suddenly they were at 6-6. Rafa had a sitter of a forehand, a stroke he delivers with punishing ease. But inexplicably he blinked. Thousands gasped as the ball greeted the net. The surprisingly fierce Frenchman hit one final down-the-line forehand winner. And that was it: after more than 4 hours the tennis pendulum swung for a final and decisive time. 2016 would be the first year Rafa would not reach a Slam quarterfinal since 2004. Yes, in the end, just two points decided a memorable battle. Then again, many a war – whether on bloody battlefields or sweaty tennis courts – is decided by the slightest of margins.