World number one Sinner was almost perfect in the opening set, making just four unforced errors, leading to the feeling that another routine win was on the cards.

But errors began to creep into Sinner's game in the second and Auger-Aliassime, who was appearing in just his second Grand Slam semi-final and first since 2021, grew in confidence - feeding off the energy of the crowd to get a foothold.

Auger-Aliassime passed up three break points for the chance to lead 2-0 but went on to break 5-3 before serving out for the set.

There had been no real indication that Sinner was carrying an injury until he left the court for treatment, although his first-serve accuracy had dropped slightly.

He landed just 10 of 25 (40%) in the third compared to 10 of 22 (45%) in the second set and 13 of 25 (52%) in the first.

Auger-Aliassime was unable to fully capitalise on any potential problem, though, and a break of serve at 5-3 was enough to take the set.

By the time the fourth began, Sinner appeared the fresher of the two - barring a few moments of resilience from his opponent.

Victory means Sinner is just the fourth player in the Open era to reach all four Grand Slam finals in a single season after Rod Laver, Roger Federer and Djokovic.

Sinner trails Alcaraz in their head-to-head record, losing nine of their 14 meetings, including three of their four encounters in 2025.

Before the final major of the season began, everyone wondered who could stop Alcaraz or Sinner sweeping the Slams for the second straight year.

Alcaraz has won back-to-back French Open titles and lifted the Wimbledon title last year, before losing to Sinner in this year's final. Now he has booked his place in the New York showpiece without dropping a set.

He broke Djokovic in the first game of the match and threatened to move a double break ahead before the Serb served his way out of trouble.

It was not a classic set of tennis, lacking absorbing rallies as points were punctuated by baseline errors. Nevertheless, Alcaraz rarely looked like relinquishing his lead.

Momentum switched at the start of the second set, however - just as it did in their Australian Open quarter-final in January.

Alcaraz dominated the first set in Melbourne, became confused as Djokovic upped the intensity in the next, and ultimately malfunctioned in a four-set defeat.

Thoughts went back to that match when Djokovic moved 3-1 up in the second set. But this time Alcaraz recognised what was happening and was able to adjust tactically and mentally.

The Spaniard ended a brutal exchange at 30-30 by casually flicking a cross-court forehand past Djokovic, bringing up a break point that his deflated opponent planted in the net.

Neither player created any more break chances, leading to a tie-break where Djokovic wiped out a 4-1 deficit for 4-3 before running out of steam.

Alcaraz had not previously lost any of the 52 Grand Slam matches where he had won the opening two sets.

It quickly became apparent that Djokovic, who asked for treatment on his neck before the third set, would not be the one to end that run.

Djokovic has built an entire career - arguably the greatest ever seen - on upsetting the status quo.

When he first emerged as a force in the late 2000s, he was the outsider looking to break up the duopoly of Federer and Rafael Nadal.

Nearly 20 years on, Djokovic finds himself squeezed out at the top of the men's game by Sinner and Alcaraz.

Alcaraz served well, and backed it up with aggressive groundstrokes early in the rallies, to overpower Djokovic in the key moments.

Former world number one Djokovic has proved this year that he still has enough left to reach the semi-finals of all four majors, but 30 unforced errors indicated the pressure he feels against Alcaraz and Sinner.

Ultimately, he will never believe he cannot win - even when the odds are stacked against him.

"They're just too good, they're playing at a high level," said Djokovic.

"I ran out of gas. I'm happy with my level of tennis - it's just the physicality of it."