When Sinner was staring at three match points with Italy 1-0 down to Serbia on Sunday (AEDT), it appeared hugely improbable that he would be lifting the trophy 24 hours later.

But the world No.4 somehow recovered to defeat Djokovic, repeated the feat in doubles along with Lorenzo Sonego and then saw off Australia’s Alex De Minaur 6-3 6-0 on Monday (AEDT) to clinch a 2-0 victory.

That sparked joyous celebrations among Sinner’s team-mates and the Italian-dominant crowd at a packed and vibrant Palacio de Deportes Martin Carpena in Malaga.

The victory earns Italy just its second Davis Cup title after success in 1976 as it continues to reap rewards from some heavy investment in men’s tennis in recent years, while for Australia it was more disappointment after its 2-0 loss to Canada in the final 12 months ago.

In Sinner, Italy has a potential superstar and it was fitting that it was the 22-year-old, who had won both singles and doubles rubbers in the quarter-finals and semi-finals, was the man to seal it.

Given Australia’s strength in doubles, though, the crucial win may have been Matteo Arnaldi’s in the opening rubber against Alexei Popyrin.

Nerves were all too evident in a clash of two young players inexperienced in the unique pressure-cooker of Davis Cup but it was 22-year-old Arnaldi who ultimately handled it better to win 7-5 2-6 6-4.

Popyrin, 24, seemed to have a grip on the match after losing the opening set and had eight break points in the decider but Arnaldi was rewarded for bold play at the big moments and it was his opponent who tightened up when it really mattered.

A tearful Arnaldi said: “It’s very emotional, more because a very important person passed away a month ago for me and my girlfriend so this is for him. I think now I won one of the most important matches in my life.

“I’m sorry for Alexei, because he deserved to win, for sure. He was playing better. But sometimes Davis [Cup] is like this. I had my team cheering a lot, and I think that helped a lot.”

Popyrin was distraught, saying: “It’s heartbreaking. I let it slip, and it hurts.”

De Minaur has a strong record in the competition but he went into the must-win clash knowing he had lost all five previous matches against Sinner.

The schedule was in his favour having had a day to prepare after a comfortable semi-final victory over Finland and there was a real spring in his step as he took to the court.

But Sinner’s big weapons quickly began to dictate proceedings, with the Italian breaking his rival’s serve twice in the opening set.

Australia captain Lleyton Hewitt, part of the playing team for its previous most recent win 20 years ago, tried to inspire De Minaur to a comeback but this was Sinner’s moment.