Carlos Alcaraz swept past Novak Djokovic to win his first Australian Open on Sunday and become the youngest man to complete a career Grand Slam, denying the Serbian great an unprecedented 25th major.

The Spaniard was imperious after a slow start in dismissing the 38-year-old, 2-6, 6-2, 6-3, 7-5 on Rod Laver Arena to claim a seventh Slam title and cement himself as undisputed world number one.

In doing so, he became the youngest man in the Open era to win all four majors, adding to his two titles each from Wimbledon and the French and US Opens.

At 22, he surpassed legendary countryman Rafael Nadal – in the crowd to witness the feat – who was two years older when he did the same.

A seventh Slam put him alongside John McEnroe and Mats Wilander and one behind Andre Agassi, Jimmy Connors and Ivan Lendl.

"It's an honour to be here in Melbourne every year," Alcaraz said, before writing on a TV camera lens: "Job finished. Four out of four complete."

"So I just want to say thank you very much for pushing me in the tough moments during the matches."

He paid tribute to Djokovic.

"You were talking about how I'm doing the things I am, but what you're doing is really inspiring, not only for tennis players but athletes around the world."

It was a first defeat for Djokovic in a Melbourne final, having won all 10 previously, leaving him still searching for a landmark 25th major to better Australia's Margaret Court, who was also watching on centre court.

Djokovic, striving to become the oldest man to lift a Grand Slam singles trophy, last won one at the US Open in 2023. Since then Alcaraz and Jannik Sinner have shared the spoils.

"I must be very honest and say that I didn't think I would be standing in the closing ceremony of a Grand Slam again so I owe you the gratitude of pushing me forward in the last couple weeks," Djokovic said, speaking to the fans in the stadium.

He went on to hint this could be his last time at Melbourne Park.

"God knows what happens tomorrow, let alone in six months or 12 months, so it has been a great ride."

He also joked with Nadal in the stands, saying: "There are too many Spanish legends. I feel like I was one against two tonight. It's not fair." (AFP)