Carlos Alcaraz equalled his best run at the Australian Open by beating Tommy Paul in straight sets to reach the quarter-finals.

The world No 1, who is yet to drop a set at Melbourne Park, has made no secret of his desire to claim the title and become the youngest man ever to complete the career Grand Slam of all four major crowns.

Having thrashed Paul in last year's French Open quarter-finals ⁠and beaten him in four sets at Wimbledon in 2024, Alcaraz gave the 19th seed ​a hard-court humbling with a 7-6 (8-6) 6-4 7-5 ​win in the afternoon sunshine at Rod Laver Arena.

Alcaraz found himself immediately on the back foot on Rod Laver Arena and he trailed 4-2 in the opening set before fighting back, while a lengthy stoppage for a medical emergency in the crowd at 3-3 in the tie-break was awkward timing for both men.

It was Paul who cracked, double-faulting on Alcaraz's second set point, and the Spaniard's extra firepower eventually carried him across the line.

"I think he started pretty strong," said Alcaraz, who bettered the record held by Bjorn Borg and Boris Becker by reaching a 14th Grand Slam quarter-final before turning 23.

"He came with really strong shots and for me it was difficult a little bit but I stayed there all the time. I knew I was going to have my chances. Overall it's been a really high level of tennis from both sides. I'm just really happy I got it in straight sets."

The improved serve that helped carry Alcaraz to a sixth major title at the US Open last summer has remained a work in progress, and the 22-year-old is particularly happy with the reliability of his first delivery.

He averaged 70 per cent first serves and won 79 per cent of those points against Paul, just a touch higher than his mark for the tournament as a whole. The Spaniard also won 68 per cent of points on his second serve.

"I'm surprising myself," he said. "The serve is something that I've been working on since a long time ago. I'm just really happy to see the improvement of the serve.

"After every set, I try to check (the statistics) out. The four matches I've played, the serve has been a really important weapon for me."

The retooled start of his service motion has a familiar look, and hasn't escaped the attention of Novak Djokovic.

The 24-time major winner joked earlier in the tournament that he has sent Alcaraz a message asking for a copyright fee.

Alcaraz was asked about it in an on-court TV interview, and played along, too.

"Yeah. I heard that. I have the contract over there but I haven't seen him yet!" the Spaniard said of his exchange with Djokovic.

Now Alcaraz must try to break new ground in Melbourne when he takes on either home favourite Alex De Minaur or Alexander Bublik.

It is the third year in a row he has reached the last eight, with Alexander Zverev and Novak Djokovic getting the better of him the last two years.

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