Barbora Krejcikova punches her fist. Jessica Pegula was moving up the court but the Czech produces a cross-court backhand passing shot which is just out of the American's reach.

A huge hold.

Barbora Krejcikova finds a first serve at the perfect moment to avoid the double break... for now.

Uh oh.

Jessica Pegula has scarcely put a foot wrong in these opening four games.

Trailing 40-15, she produces a cross-court backhand winner which lands maybe an inch inside the baseline before forcing the error from Barbora Krejcikova with a booming return to bring up deuce.

It's a slightly messier service game from Jessica Pegula, including a double fault for 40-30.

However, she completes the hold and is doing an excellent job of playing to the full extremities of the court. She's stretching Barbora Krejcikova across the baseline and dragging her from corner to corner.

Barbora Krejcikova double-faults to hand Jessica Pegula an early break.

Jessica Pegula takes a 0-30 lead, standing on the baseline and pummelling the ball back to Barbora Krejcikova's forehand again and again.

And then, Krejcikova air-shots an attempted smash to bring up three break points for the American.

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

It's interesting to see Krejcikova using that slice backhand this early in the match. She has used two already and it drew out an error.

A routine hold to 15 for Jessica Pegula.

She's already crept up the court a few times, including sealing the game with a forehand volley. She's showing her intent early.

Jessica Pegula is serving first to get this US Open quarter-final under way.

* denotes next server

Image source, Getty Images

Barbora Krejcikova’s road to the quarter-finals has been just a little more dramatic than Jessica Pegula’s.

After beating Victoria Mboko and Moyuka Uchikima in straight sets, she had to come from a set down against 10th seed Emma Navarro to book her spot in the second week.

In the fourth round, she was down and out against Taylor Townsend, losing six consecutive matches to concede the first set 6-1 and facing eight match points in the second before storming back to win in three sets (1-6 7-6 (15-13) 6-3).

The match lasted three hours and six minutes while Pegula’s fourth round victory over Ann Li took just 54 minutes.

Image source, Getty Images

Jessica Pegula headed into the US Open with just two wins from her past four tournaments but has rediscovered her form at the perfect time.

The 2024 runner-up hasn’t dropped a set on her run to the last eight, brushing aside Mayar Sherif, Anna Blinkova, Victoria Azarenka, and Ann Li, and has only lost 17 games in four matches.

If she reaches the semi-finals, she’ll do so without facing a player ranked inside the top 50.

However, she has already beaten a former world number one and two-time Grand Slam singles champion in Azarenka (round three) while her latest opponent – Krejcikova – is a former French Open (2021) and Wimbledon (2024) champion in singles.

Jessica Pegula loves playing on home soil.

The US Open is the only major where she’s progressed beyond the quarter-finals in the singles draw, reaching last year’s final, while since the start of 2023, 10 of her 21 tournament semi-final appearances have come in USA.

However, the fourth seed is up against a tricky opponent in the last eight. Not only is Barbora Krejcikova a former world number two and a 12-time Grand Slam champion across the disciplines, she’s also on a roll when it comes to knocking out home favourites.

After beating Americans Emma Navarro and Taylor Townsend in the previous two rounds, she’ll be looking to make it three in a row against Pegula.

Krejcikova leads their head-to-head 2-1, most recently winning 6-3 6-3 at last year’s WTA Finals in Riyadh.

Up first at Arthur Ashe Stadium, it's American fourth seed Jessica Pegula against Barbora Krejcikova.

BBC Radio 5 Sports Extra 2

BBC Radio 5 Sports Extra 2 has live commentary of day 10 in New York.

Coverage is also available via BBC Sounds or by clicking the link at the top of this page.

Women's Singles Quarter-Finals

Aryna Sabalenka (1) v Marketa Vondrousova

Jessica Pegula (4) v Barbora Krejcikova

Karolina Muchova (11) v Naomi Osaka (23)

Amanda Anisimova (8) v Iga Swiatek (2)

Men's Singles Quarter-Finals

Jannik Sinner (1) v Lorenzo Musetti (10)

Felix Auger-Aliassime (25) v Alex de Minaur (8)

Novak Djokovic (7) v Taylor Fritz (4)

Jiri Lehecka (20) v Carlos Alcaraz (2)

Image source, Getty Images

Naomi Osaka put on an impressive display to knock out American third seed Coco Gauff in just over an hour.

World number one Jannik Sinner needed only 81 minutes to cruise past Alexander Bublik in straight sets.

Canadian Felix Auger-Aliassime provided an upset by beating 15th seed Andrey Rublev in straight sets to set up a quarter-final tie with Alex de Minaur, who eased his way past Swiss qualifier Leandro Riedi.

Meanwhile, Italian Lorenzo Musetti knocked out Spaniard Jaume Munar in straight sets.

World number two Iga Swiatek battled past Anna Kalinskaya in her women's singles round of 16 match, coming through a first set tie-break before winning the second set 6-4.

American Amanda Anisimova brushed aside Brazilian 18th seed Beatriz Haddad Maia, dropping just three games in a straight-sets win, and 11th seed Karolina Muchova beat Marta Kostyuk in three sets.

Hello there! It's day 10 of the US Open and time for the quarter-finals in the men's and women's singles.

There's plenty of big names left in both draws, including Jannik Sinner, Carlos Alcaraz, Aryna Sabalenka, Iga Swiatek, and Novak Djokovic.

Let's get started!