Coco Gauff became the first American teenager to win the US Open title since Serena Williams in 1999 when she triumphed here three years ago.

The 22-year-old, who also won the French Open last year, is aiming to reach the fourth round at her home slam for a fifth straight year.

She will be in star-studded company if she becomes only the fifth American woman to achieve that before the age of 23, after Chris Evert, Tracy Austin, Pam Shriver and Venus Williams.

Gauff makes a positive start, forcing an early break point, but Cristina Bucsa avoids an early setback.

Image source, Getty Images

Marie Bouzkova is not going anywhere.

She continues to do what she has to do and eases the pressure with a love hold.

Back over to you, Iga...

Where did that come from?

Iga Swiatek is 40-0 up and poised to level the second set on moment, the next she is having to save break point.

There is no sign of frustration from the former champion, though, she sticks at it, saves break point and - despite the very impressive durability of Marie Bouzkova - fights her way to a hold.

After all that, we are all square in the second.

Coco Gauff is serving first in this one and gets off to a tidy start.

The American dictates the early exchanges, and takes the opening game to love with a final backhand down the line.

A positive, assured start.

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Coco Gauff's bid to win a second US Open title continues against Spain's highest-ranked player Cristina Bucsa.

Gauff has reached the third round for the fifth consecutive year, having come through a tough encounter with Paula Badosa.

Badosa had won their previous two meetings, so Gauff believes that win will be good for her confidence when faced with tough tests.

"I think it's good to be battle-tested," Gauff said.

"When I won here in 2023, I think I went three sets almost every match. When I saw the draw, I knew if I got through my first-round match, the second round was just going to be tough regardless.

"I think for me it's a good confidence booster knowing that I can get through these matches."

Iga Swiatek hits back again!

A real slog of a game for both players. Marie Bouzkova dug in to save the first of two break points but can stave off the second.

Swiatek changed things up nicely there, not just sticking with the all-out power that Bouzkova had become used to, and it pays off.

Back on serve once again.

Significantly later than she would have been expecting when compatriot Taylor Fritz took a two-set lead on Arthur Ashe Stadium two hours ago, Coco Gauff will soon attempt to lift the home support on the US Open's main stage as she resumes her title bid against Cristina Bucsa.

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Francisco Cerundolo speaking after beating Taylor Fritz: "Fritz was playing way better than me in the first set, he was really aggressive, I wasn't feeling confident but I broke back into it in the third set and I started getting into it step by step.

"In the fourth and fifth I played really good tennis. Taylor is a top player, he played a final here and won a lot of matches so I knew how difficult it is to play against him. Winning here on my first time on Ashe is fantastic."

Marie Bouzkova just grinds you down, she's not going to hit too many winners but you can be pretty certain she'll get the ball back in play.

That means the onus is on her opponent to hit winners, Iga Swiatek is only too happy to try but she doesn't get it right in this game.

Three times she is loose with her forehand, each time going long, and Bouzkova has the break advantage again in the second set.

No sooner was she in a spot of bother, Iga Swiatek brings it back on serve in the second.

It's real frustration for Marie Bouzkova, who worked so hard to stay in the point with relentless side-to-side defence on the first of two break points, as she gifts Swiatek the second with a double fault.

Pam Shriver
Five-time Wimbledon doubles champion on BBC Radio 5 Live

That changes again the lower part of the men's draw where Flavio Cobolli, the fifth seed, is playing Blockx. I mean it is the opportunity time in men's tennis, Alcaraz looking so secure now on the other half of the draw.

Taylor Fritz exiting, that is a big shock as far as the US men go. We have other US men who are hoping to end this run of not winning a major for the last 23 years.

It was interesting to see Fritz rip off that headband in disgust. Last year he put it on upside down, he'll be hoping things went a bit more upright for him in that match.

Iga Swiatek is on the board in this second set.

Much better from the eighth seed. A superb forehand finds the corner on Marie Bouzkova's forehand side, too good for the Czech this time, and it's a hold to love.

Well, suddenly Marie Bouzkova is on a roll!

The Czech has barely put a foot wrong so far in this second set and holds to 15 to go up 3-0.

Iga Swiatek has work to do if she's to avoid a deciding third set.

Marie Bouzkova is really putting on the pressure at the start of this second set!

She takes it to deuce and then brings up two break points but each time Iga Swiatek finds the answer.

The 2022 champion can't manage it a third time, though. A brilliant point with Bouzkova able to deal with everything Swiatek throws at her before the Pole eventually finds the net.

Taylor Fritz's US Open hopes are hanging by a thread here!

The American ninth seed, from two sets up, is a break down in the fifth set.

Francisco Cerundolo breaks to 15 after Fritz makes his latest mistake in an error-strewn performance, and will now serve to complete a quite remarkable comeback after more than three-and-a-half hours on Arthur Ashe Stadium.

The home support have fallen silent. This did not appear on the cards.

Image source, Reuters

Pam Shriver
Five-time Wimbledon doubles champion on BBC Radio 5 Live

Coco Gauff has been Taylor Fritz's partner in the United Cup. She would be pretty upset with what has unfolded here.

Just what Marie Bouzkova needed after losing that tie-break.

She puts away an overhead smash to seal a hold to love to begin the second set.

Emphatic.

Alexander Blockx sends Flavio Cobolli for a bagel in New York to take a two-sets-to-one lead over the Italian fifth seed.

Belgian Blockx won 24 of the 28 points they played in an 18-minute third set, winning 100% of points behind his first serve.

Cobolli trudges off court. If he is going to reach the US Open fourth round for the first time, he is going to have to do it the hard way, against an opponent who is completely locked in here.

All credit to Blockx. The 28th seed is playing at an incredibly high level on Louis Armstrong Stadium.

She's done it the hard way but Iga Swiatek takes the first set.

Three times the Polish eighth seed had to come from a break down, including when Marie Bouzkova was serving for the set, but she comes through in the tie-break.

Bouzkova will see it as a missed opportunity, Swiatek has shown her resilience.