Annabel Croft
Former British number one on BBC Radio 5 Sports Extra 2

I think it will be fascinating mentally, how much this match will get to Rybakina.

There are also fourth-round matches taking place in the men's singles at the US Open today.

Argentina's Francisco Cerundolo, who fought back from two sets down to beat Taylor Fritz in the previous round, dropped the first set against Belgium's Alexander Blockx on Arthur Ashe Stadium but won the second to level at one set all.

Elsewhere, unseeded pair Arthur Gea and Botic van de Zandschulp will soon be getting their fourth-round match under way on Grandstand, with top seed Alexander Zverev a potential quarter-final opponent for the winner.

Zverev plays Luciano Darderi in the night session, while home favourite Learner Tien will take on Karen Khachanov after the Osaka-Rybakina match concludes on Louis Armstrong Stadium.

Simple as you like for Naomi Osaka.

She gets herself on the board with a hold to love in double-quick time.

There's an early prospect of a break for Naomi Osaka as she wins the first two points of the match on Elena Rybakina's serve.

However, Rybakina didn't get to the brink of the world number one spot by panicking in such situations and calmly works her way through the rest of the game.

A hold to 30 to get things started.

Image source, Getty Images

While Elena Rybakina's main aim at Flushing Meadows is clearly to try and secure a third Grand Slam title, it is not her only goal.

The 27-year-old second seed is also hoping to leave New York as the world number one.

Just reaching the semi-finals would be enough to see her overtake Aryna Sabalenka in the rankings, regardless of whether the Belarussian defends her title.

"I'm definitely motivated [to become world number one]," Rybakina said after her first-round win over 17-year-old wildcard Thea Frodin.

"I feel like I had opportunities before and it didn't go my way. It will be an amazing achievement but it's still too far and I need to focus on my day off tomorrow, my recovery, and just keep on going."

Should none of Sabalenka, Coco Gauff or Jessica Pegula win the title, Rybakina will ascend to the top of the rankings regardless but she is two wins away from making absolutely sure.

Image source, Getty Images

Naomi Osaka has really had to fight to make it through to the fourth round in New York.

The two-time US Open champion started with a 7-6 7-6 win over Anastasia Zakharova before being taken to three sets by Katerina Siniakova and Elise Mertens.

But having made it this far, there is no doubt Osaka is battle-hardened for the latter stages of the tournament as the prospect of a fifth Grand Slam title edges ever closer.

If she can get past second seed Elena Rybakina, who has breezed through to this stage without dropping a set, then Osaka will have every reason to believe.

Rybakina won the only previous meeting between these two, coming from a set down to win in three in Toronto just a few weeks back.

Image source, Reuters

Well, this has become a big moment of any Naomi Osaka match: her entrance onto the court and, specifically, her outfit.

She walks out in another eye-catching jacket with art of some sort on it and a fur (or faux fur) collar.

Sorry, this is why I write about sport rather than fashion!

Right then, back to the match at hand...

Image source, Getty Images

French Open champion Mirra Andreeva was severely tested by Anastasia Potapova until the 24th seed injured her knee in what proved to be the final game of their match on Louis Armstrong Stadium.

Potapova seemed to twist or hyperextend her knee while attempting to hit a ball on the run from the baseline and Andreeva was across quickly to check on her grounded opponent.

Potapova returned to the court after receiving treatment but lost the remaining points in her service game, confirming her exit from the tournament.

Fifth seed Andreeva, who won 5-7 6-4 6-3, said: "Anastasia is my good friend and seeing what a battle we had and seeing her fall like that in the last game, it's not easy.

"I told her that she's been playing amazing and having one of her best seasons. I'm sure she'll come back even stronger - she's a warrior and an even better fighter than me."

Image source, Getty Images

Whoever wins the upcoming match between Naomi Osaka and Elena Rybakina will face China's Zheng Qinwen in the quarter-finals.

Zheng won a set from 5-0 down for the second match in succession as she extended her fantastic US Open run by beating former champion Iga Swiatek 7-5 6-3.

The reigning Olympic champion and former world number four dropped outside the top 100 earlier this year while struggling to regain her best form following elbow surgery in July 2025.

The 23-year-old had trailed Madison Keys 5-0 in the deciding set of their third-round match on Saturday before winning seven successive games to secure her spot in round four.

And qualifier Zheng was again 5-0 down in the opening set against Poland's eighth seed Swiatek, but won 13 of the next 16 games on Arthur Ashe Stadium.

The second set was on serve until the seventh game, when Zheng crushed a powerful backhand return winner to secure a crucial break, and she broke again two games later to complete a victory that will move her back to the brink of the top 50.

I hope you all used your break wisely...

We're back and fully refreshed for what should be a cracking match on Louis Armstrong Stadium.

Four-time Grand Slam champion Naomi Osaka is aiming to take the title at Flushing Meadows for a third time but to make it to the quarter-finals, she'll have to get past second seed Elena Rybakina.

So get yourself settled, I've got high hopes for this one!

We're going to park our live text coverage for now but we'll be back later for two-time US Open champion Naomi Osaka's fourth-round match against second seed Elena Rybakina.

That match is third on Louis Armstrong Stadium and due to start after the women's doubles match between Katerina Sinakova and Taylor Townsend, and Storm Hunter and Desirae Krawczyk, which has just got under way.

See you soon!

Daniela Hantuchova
Former world number five on BBC Radio 5 Sports Extra

Wow. Zheng just doing the incredible magic. She has already done so much in her career but this must be one of her most special victories given where she has come from. It is like an Emma Raducanu fairytale right there.

Image source, Reuters

Zheng Qinwen speaking on court after beating Iga Swiatek: "I have to say I started the match not so well but after I found my rhythm on the centre court - because it has been a long time since I have played here. I just really appreciate being here.

"I focused point by point and little by little, I played better tennis and I started to find my game. At one moment, I even forget the score, that shows my focus.

"I think the baseline I tried to play more flat against her because she has a really good topspin and she makes me feel uncomfortable. I tried to play more aggressive. I am really happy to win this match because it was not easy.

"The more matches I play, the more rhythm I get. I just feel really pumped and ready for my next match."

Mirra Andreeva speaking on court after beating Anastasia Potapova: "She is my good friend and seeing what a battle we had, then seeing her fall is not easy. I can't imagine what she's going through.

"It's not the way you want to finish the match but I just told her that she's been playing amazing and that I'm sure she'll come back even stronger. She's a warrior.

"I'm super happy that I was able to find motivation inside myself to fight. It was not easy, I didn't really know what to do to beat her in the first set because she had answers to everything I was playing.

"Happy to win but still pretty sad with how it ended."

A couple of wayward shots from Iga Swiatek put her in trouble, before the Pole goes long with a forehand to offer three match points to Zheng Qinwen.

Swiatek recovers brilliantly though to force deuce, the pick of the points being a superb forehand winner down the line.

Zheng Qinwen is playing really well now and a couple of unplayable serves puts her in control of the game.

She wraps it up in style, stepping inside the court to put away a backhand winner across the court.

The crowd roar and Zheng is one game away from the quarter-finals.

Daniela Hantuchova
Former world number five on BBC Radio 5 Sports Extra

What is most impressive is the reaction after just breaking Iga. She is so composed and so dialled in. She is not wasting energy on anything else, which is very different from what we are seeing on the other courts.