US Open day seven - listen to BBC Radio 5 Sports Extra commentary (UK only)
LIVE: Defending champion Carlos Alcaraz 6-4 6-3 American Tommy Paul
Second seed Alcaraz bidding for third New York title and eighth major overall
Wimbledon champion Linda Noskova wins 7-5 5-7 6-4 against Marta Kostyuk to set up quarter-final with world number one Aryna Sabalenka
Sabalenka beat home hope Taylor Townsend 6-4 6-3 to continue quest for third straight title
She must win title - and hope Elena Rybakina loses before semi-finals - to keep world number one ranking
GB's Harry Patten into third round of doubles alongside Finland's Harri Heliovaara
*Paul 4-6 3-6 0-0 Alcaraz
Carlos Alcaraz wraps up a set in which he has dominated.
Just brilliant from the seven-time major champion.
A double fault to start the game briefly gives Tommy Paul hope but that is soon snuffed out.
Alcaraz has simply been too good.
Paul 4-6 3-5 Alcaraz*
Jeff Tarango
Former American tennis player on BBC Radio 5 Live
I think he should be getting a lot more height on some of his balls, above Alacarz's shoulders. He then has to work that ball even more and then he can't hit those thunderous surprise shots.
Going soft, soft, soft and then boom. He's able to dictate his own shots. Tommy's got a great slice, just keep mixing it up a little bit. It's like Tommy is playing a pattern and it's not working.
Paul 4-6 3-5 Alcaraz*
Six service games in a row now, Tommy Paul has gone down 0-30.
He's not making things any easier for himself.
But an ace and another thumping serve take it to 30-30 and he goes on to hold.
Carlos Alcaraz will have to serve for the second set.
*Paul 4-6 2-5 Alcaraz
The disappointment of failing to convert all those break points in the last game didn't last long for Carlos Alcaraz.
He dominates throughout his service game and even when Tommy Paul looks sure to win the point at 40-15, the defending champion shows remarkable defence.
He keeps the point going and eventually it is Paul who errs first. Alcaraz is one game away from a two-set lead.
Michelsen 3-0 Etcheverry*
While Tommy Paul is battling hard to stay in his fourth-round match against Carlos Alcaraz, another American - unseeded Alex Michelsen - has made a fine start to his last-16 contest on Grandstand.
Michelsen broke Tomas Martin Etcheverry of Argentina, the 27th seed, at the first attempt and leads 3-0 in the opening set.
Michelsen, 22, has never got to a Grand Slam quarter-final before.
Paul 4-6 2-4 Alcaraz*
Image source, Getty ImagesThat is some hold for Tommy Paul.
A set and a break down already, down 0-40 and he shows mightily impressive resilience to save a total of six break points in the game.
The crowd on Arthur Ashe Stadium show the American their appreciation.
Can this be the start of a comeback for Paul? Carlos Alcaraz will have other ideas.
Kostyuk 5-7 7-5 4-6 Noskova
Image source, ReutersLinda Noskova after winning against Marta Kostyuk, an opponent she knows very well: "I am more than relieved, this match was so tough, emotionally a bit more than physically.
"We did play for more than two hours, we were defiantly going since the start but there was a lot of crucial points."
On having 11 grand slam victories in a row: "Today was very close it could have ended both ways, Marta she's a huge competitor, I knew it was going to be tough. With all the chances I had in the second set, it was tough to still kind of restart."
Paul 4-6 1-4 Alcaraz*
Tommy Paul is clinging on for dear life now.
He reaches Carlos Alcaraz's drop shot but the Spaniard then reads the passing shot and produces a stunning reaction volley and brings up three break points.
Paul digs deep to save all three, only for Alcaraz to bring up another with a magnificent backhand down the line on the move for a winner.
The American saves that with a massive 138mph serve but on we go...
Kostyuk 5-7 7-5 4-6 Noskova
Jeff Tarango
Former American tennis player on BBC Radio 5 Live
Now Kostyuk looks tired. It's almost like the relief of it, she can show she's tired. This crowd really favouring Kostyuk but the Wimbledon champ shows by just pure greediness that she was going to win the match.
She didn't have a doubt whether she was going to win or lose, it was just how long was it going to take.
*Paul 4-6 1-4 Alcaraz
Break consolidated this time.
Carlos Alcaraz is feeling it now. He throws in a serve and volley to give Tommy Paul something else to think about, moving up 40-15.
The Spaniard then drills a forehand down the line before moving in and creating a brilliant angle to go cross-court.
Paul can barely reach it and he can feel the second set slipping away from him.
Kostyuk 5-7 7-5 4-6 Noskova
Image source, ReutersLinda Noskova drops to the floor.
On a sixth match point, about an hour after her first, the Wimbledon champion has done it!
A first US Open quarter-final is hers after surviving an emotional rollercoaster against Marta Kostyuk, who certainly played her part in a thrilling match.
Paul 4-6 1-3 Alcaraz*
Carlos Alcaraz wastes no time in regaining the break advantage in the second set!
With Tommy Paul's serve faltering, Alcaraz brings up two more break points with a gorgeous lob.
He then finds the line with a stinging forehand - the crowd can't believe it's in and Paul does well to get it back over the net... but it drops wide and the defending champion reasserts his control.
Kostyuk 5-7 7-5 4-5 Noskova*
Marta Kostyuk is hanging in here... again! Linda Noskova covers her face with her hand after missing two more match points - her third and fourth overall after she failed to seal victory in the second set.
This is agony for the sixth seed, but it gets worse as Kostyuk reaches break point.
Noskova holds her nerve to save that, and earn a fifth match point.
Kostyuk says no again! It's hands-on-face time again for Noskova. Surely this can't slip away again?!
*Paul 4-6 1-2 Alcaraz
Image source, Getty ImagesTommy Paul needed that!
He gets the break back immediately, just at the moment it seemed the match was getting away from him.
Carlos Alcaraz saves the first break point but is wide with a forehand on the second. Back on serve in the second set.
*Paul 4-6 0-2 Alcaraz
Now then...
Carlos Alcaraz finds the net with a backhand and Tommy Paul has two break points.
Big moment in this match, especially for the American, you feel.
Paul 4-6 0-2 Alcaraz*
David Law
Commentator on BBC Radio 5 Sports Extra
Alcaraz is turning it on here, it's quite something to behold.
Tommy Paul just smashed down a 136mph serve, Alcaraz got it back, another from Paul and a forehand that was probably about 136mph from Alcaraz.
He's broken for two love, he's roaring away from Paul now.
Kostyuk 5-7 7-5 4-5 Noskova*
Once again, Linda Noskova is one game away from a place in the US Open quarter-finals.
Can she get over the line this time?
Marta Kostyuk will not go quietly. Just as she did late in the second set, the 11th seed holds serve to give herself the chance to test Noskova's nerves.
Paul 4-6 0-2 Alcaraz*
Image source, Getty ImagesThat's extraordinary from Carlos Alcaraz!
Somehow he gets a 136mph serve back and then follows it up with a rocket cross-court forehand.
It just finds the line with Tommy Paul helpless and that brings up three break points.
He needs just one, coming in to slap a forehand winner. Worrying moments for Paul.
*Paul 4-6 0-1 Alcaraz
The chance was there for Tommy Paul, just briefly.
Up 15-30, the American 20th seed gets a look at a second serve but the return lets him down.
Carlos Alcaraz comes through to hold and keep the momentum.
Kostyuk 5-7 7-5 3-4 Noskova*
Jeff Tarango
Former American tennis player on BBC Radio 5 Live
When Kostyuk won that second set she was all smiles, giggles and laughing and her smile has really gone away.
