Novak Djokovic may still be the best player in men’s tennis but, in the self-inflicted absence of the world No1, Dominic Thiem, 27, can fairly lay claim to be leading the charge of the new wave of contenders after beating 23-year-old Alexander Zverev to win the 2020 US Open on Sunday evening.

Djokovic, 33, is waiting with 34-year-old Rafael Nadal for these impatient arrivistes to show up on the clay of Rome this week (Roger Federer remains at home resting his 39-year-old knees), and beyond that lies Roland Garros, the postponed and final slam of a disjointed, crazy season. Whatever Federer and Serena Williams believe, age is not just a number; it’s a pain in the backside.

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The old guard could only watch from a distance in their various hotel rooms or mansions as Thiem won a grand slam final at the fourth attempt, outlasting his opponent 2-6, 4-6, 6-4, 6-3, 7-6 in exactly four hours in front of family, friends and staff in the virus-cleansed Arthur Ashe Stadium. He is the first player in 71 years to come from two sets down to win the title.

Thiem told his long-time friend on court, “We started to know each other back in 2014 and developed straight away a great friendship, and 2016 our rivalry started. We made great things happen on the court and off the court. I wish we could have two winners today. We both deserved it. You’re going to make it, 100%, make your parents proud.”

Zverev, struggling to contain his tears as he spoke of missing his parents, said, “It was a tough battle, but here I am giving the runners-up speech. I wish one day I can bring the trophy home.”

Thiem, the 55th men’s slam champion of the Open era, is the first newcomer at the top table since Marin Cilic won his first and only major so far by breaking the spell of the Big Three here in 2014.

The US may be the land of tumult and change, but the men’s game is still ruled from Europe; all 43 men’s champions over the past decade have come from the “old world”. And that’s where the next chapter of the 2020 season will be played out.

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Thiem’s early mobility was slowed by a pre-existing achilles problem although he was hardly a sitting duck. Still, few imagined Zverev would break down the Austrian’s game the way he did. The German struck a string of aces and booming forehands, as expected, but he threw in subtle changes of pace and depth to keep his opponent guessing in their 10th encounter.

Zverev came to his first slam final brandishing by far the bigger weapons: 116 aces to Thiem’s 41 (the same as Naomi Osaka, 29 fewer than Serena Williams). But nobody in the draw came close to Zverev’s 49 double faults, and his shaky second serve returned to haunt him in the later stages of the match.

Not always a confident or quick starter, he gave up just three points on his serve in the first set, broke Thiem twice and, with four aces among 16 winners, took the frame in half an hour to establish the ideal platform.

In the third game of the second set, Zverev struck a 103mph forehand on his way to another spirit-sapping break, and was comfortably on top of every aspect of his game. Thiem was drowning.

In the final in Melbourne this year, Thiem found reserves that stretched Djokovic to the limit in a five-set fight the Austrian came close to winning. He did not need reminding here that he was one of only five players to start 0-3 in slam finals.

Pinned behind the baseline, he dropped serve to trail 1-4. Inside an hour, he looked out of contention – but the most stubborn fighter on the tour saved two break points to extend the second set past the hour, broke back and held to love for 4-5. But, no sooner had tension invaded the near-empty Arthur Ashe stadium, than it floated away on the early evening breeze, as Zverev gambled on a de-fanged serve to finish the job for a two-set lead.

Just as Thiem’s resistance looked to be ebbing, he exchanged breaks in the third. He was going to make his friend sweat. Now each game was close, each point treasured. Zverev held through deuce in the eighth game but his serving jitters returned at the worst moment and he handed Thiem the set on a plate.

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The early certainty had vanished, the rallies grew longer – which suited Thiem more than Zverev, who must have thought the title was his when he was two sets up. Behind in the serving cycle, he had to convince himself he could win with the passing of each close game. Where once there was demolition, now there was excavation as Zverev repeatedly had to dig himself out of holes in the fourth set.

The nerves continued to rattle at both ends but more loudly for Zverev, and Thiem served out to love to level at two sets apiece. Only four slam winners have come back from two sets down in the Open era, all of them at the French Open, but it was Zverev who appeared to be weighed down by history.

Zverev’s head dropped when he shoved a forehand wide to drop serve at the start of the deciding frame but Thiem, who had recorded 13 double faults in six matches, struck his seventh of the night to return the favour. There is no pressure quite like the final of a grand slam.

A 15th ace, struck with the kind of conviction that had been missing for at least an hour, kept Zverev in front. Thiem’s serve wobbled with an eighth double fault, but he fashioned a shaky hold for 3-3 with some venomous groundstrokes. This was a gambler’s nightmare.

Thiem finally cracked for 3-5, pushing a weary backhand into the tramlines, and Zverev stepped up to finish a job he should have put to bed much earlier. He was two points from the championship but butchered a volley and the match stayed alive.

Limping again, Thiem found two remarkable winners to hold for 5-5, then forced another break and stepped up to serve for the title. Almost on cue, the plot twisted once more, Zverev breaking to force the tie-break.

And there the drama was condensed into 14 points, Zverev gifting two of them to his opponent with double faults, Thiem wasting two match points before fashioning another and watching Zverev’s final backhand drift harmlessly wide to end a curious but significant final.