NEW YORK (AFP) — Defending champion Carlos Alcaraz posted his most convincing win in his injury return at the US Open, downing Tommy Paul in straight sets on Sunday to reach the quarterfinals.

Two-time women's defending champion Aryna Sabalenka also advanced, lining up a quarterfinal clash with Wimbledon winner Linda Noskova.

Second-seeded Alcaraz, playing his first tournament since he was sidelined by a right wrist injury in April, looked closer to his brilliant best in a 6-4, 6-3, 6-4 victory over Paul, the 20th-seeded American who posed the Spaniard's sternest test yet.

"I played my game," said Alcaraz, who unleashed 33 winners as he moved fluidly around the court in the two-hour 20-minute match.

"I tried to play my style," he said. "Tommy is such a talented player. His shots are pretty dangerous and sometimes it's really difficult to control the ball when it comes to you.” 

"I just tried to be ready for a battle and tried to be aggressive all the time."

Alcaraz grabbed the first break of the contest in the final game of a tight first set.

From there he was in control. He broke Paul twice in the second set and again early in the third.

He finished it off with a gutsy hold of serve in which he saved a pair of break points, the second with a swinging forehand volley that he followed with a forehand winner to set up the only match point he needed.

"I'm really happy with the performance today," said Alcaraz, who next faces either in-form eighth-seeded American Ben Shelton or resurgent Greek Stefanos Tsitsipas.

Sabalenka kept her bid for a rare US Open three-peat on track with a 6-4, 6-3 victory over American Taylor Townsend.

The Belarusian, whose world No. 1 ranking is on the line in New York, will face a tough quarter-final against sixth-ranked Czech Noskova, who edged dangerous Ukrainian Marta Kostyuk 7-5, 5-7, 6-4.

Sabalenka needed all of her resolve against the multi-faceted Townsend, whose blistering service returns and net prowess flummoxed the Belarusian star in a first set that opened with five breaks of serve.

Sabalenka managed a comfortable hold for a 4-2 lead and eventually her sustained power and precision proved a little too much.

"What an incredible player she is, approaching the net, what a great returner, moving well, very brave," Sabalenka said. "You can see how focused she was and it was really challenging playing her, especially here."

The second set unfolded in traditional style, neither player facing a break point through the first three games.

Sabalenka blinked first, surrendering a break that gave Townsend a 3-1 lead. But she broke back immediately, launching a run of five straight games to take the match.

"I was just trying to stay focused on myself and play not only point by point but ball by ball," Sabalenka said. "I'm happy that I was able to turn around that second set."

Noskova needed six match points to seal her victory over Kostyuk, failing to convert two in the second set.

"I am more than relieved," Noskova said. "This match was so tough, emotionally more so than physically." 

Former champion Daniil Medvedev of Russia, seeded seventh, faced charismatic American Frances Tiafoe on Louis Armstrong Stadium.

Tiafoe, the 11th seed who has twice reached the semi-finals in Flushing Meadows, booked his quarter-final berth with a 7-6 (7/1), 6-4, 7-6 (8/6) victory over Medvedev.

Brimming with confidence after a US Open build-up that included a runner-up finish in Cincinnati, Tiafoe will face compatriot Alex Michelsen for a place in the semi-finals.

Michelsen defeated Argentina's Tomas Martin Etcheverry 7-6 (8/6), 6-4, 6-4.

In other matches, third-ranked Jessica Pegula — one of the players with a chance to supplant Sabalenka atop the rankings in New York — took on Romanian veteran Sorana Cirstea, who is enjoying one of her best seasons in 2026 since announcing it would be her last.