Carlos Alcaraz has beaten American 20th seed Tommy Paul 6-4, 6-3, 6-4 to reach the quarterfinals of the US Open and remain ​firmly on track for back-to-back titles at Flushing Meadows.

The seven-time grand slam champion has hit top form in New York after nearly five months out with a right wrist injury and extended his major match-winning streak to 18 with a stunning display of shot-making.

It included a blistering 164km/h forehand winner down the line as he established an advantage early in the second set on Arthur Ashe Stadium. 

For a man who missed the past two slams and has been out since April due to a wrist injury, an ailment that had ended or stunted multiple tennis careers, it was an indicator that he is back to "full power".

It was one of 33 winners for Alcaraz, including another rocket of a forehand to bring up match point at a venue where he has thrived ever since his maiden major triumph four years ago.

"I think so," ⁠Alcaraz said when asked about being back to his best in New York, where he has reached the quarterfinals in five of his six ‌appearances now.

"It shows ‌how special this place is to me. I'm just trying to enjoy my time on the court, so it probably doesn't matter that I was out for four and a half months.

"Every time I come here, I play my best."

Despite the scoreline, Alcaraz was pushed by the speed demon on the other side of the net, with Paul pulling out his second around-the-post winner of the tournament.

The Spaniard was unfazed.

"I think I ‌just played my game," Alcaraz said.

"I tried to play to my style. Tommy's such a talented player and his shots are pretty dangerous and it's difficult to ‌control the ball when it comes to you. I was ready for a battle.

"I was trying to ⁠be aggressive all the time … I did well to put pressure on his ‌return, which helped me stay calm and to ​think clearly. I was really ‌happy with the performance."

Even with much of the showcourt crowd yearning for ‌a home winner, second seed Alcaraz ‌continued to steal the show with his audacious play and moved to the brink of improving his win-loss record against ‌American players at the grand slams to 13-0.

After shifting down to cruise mode, Alcaraz briefly flinched at the finish line, but he regrouped to deliver the knockout blow and set ‌up a ​meeting with American Ben Shelton, who swept aside Greece's Stefanos Tsitsipas 6-2, 6-3, 6-4.

On the other side of the draw, Frances Tiafoe beat Daniil Medvedev 7-6(7/1), 6-4, 7-6(8/6) to set up an all-American quarterfinal with Alex Michelsen.

The 22-year-old beat 27th-seeded Argentinian Tomas Martin Etcheverry 7-6(8/6), 6-4, 6-4 in their fourth-round clash.

Reuters/ABC