05:12 PM BST
Boulter breaks again
The Briton is in control here and has just broken Parry again to go 3-0 ahead in the second set.
She leads 6-4, 6-3.
05:08 PM BST
Berrettini takes the first set
Berrettini has won the first set on court five against Humbert.
The cheer from the adjacent court was so loud that Boulter did not hear the umpire on her court call “let” on her serve.
There has been much talk about the US Open being the noisiest tournament thanks to planes and trains, but it seems fans are also in on the act.
Elsewhere, Zverev has also taken his first set, while Jabeur is serving for the set.
04:58 PM BST
Boulter breaks straightaway
Boulter wastes no time in the second set, breaking Parry in the first game to go 0-1 ahead.
04:57 PM BST
Boulter takes the first set 6-4
Boulter smashes a forehand across court to take the first set 6-4.
A measured start from the Briton, who required just one break to take the set. But it was her serve that began to fire to close it out.
She will hope to maintain her powerful service game as her first-round match progresses.
04:49 PM BST
Boulter does well to hold serve
Immediately after being broken, Parry worked Boulter hard in an attempt to break back, pushing her to a third deuce.
But the British player showed her steel to come back from break point and hold serve, going 5-3 ahead in the first set.
04:44 PM BST
Elsewhere in their first sets, Jabeur leads Osorio 4-3, Fernandez is 4-2 up against Ekaterina Alexandrova and Italy’s Matteo Berrettini is 4-2 ahead against France’s Humbert. Zverev also leads Vukic 4-2.
04:38 PM BST
Boulter breaks in the first set
Katie Boulter plays three forehand winners in the game to break Diane Parry.
Boulter leads 4-3 in the first set.
04:33 PM BST
Laura Sigemund slams crowd for showing “no respect” after Coco Gauff loss
Earlier on Arthur Ashe, fans were treated to a three-set thriller between Laura Sigemund and Coco Gauff which included a 26-minute game at the start of the second set.
The American, Gauff, eventually recovered from a set down to win 3-6, 6-2, 6-4.
Speaking at a press conference afterwards, the German Siegemund criticised the US Open crowd for showing her “no respect” during her first-round defeat.
Check out Siegmund’s full response below.
04:25 PM BST
Murray sizes up “volatile” opponent
Andy Murray must overcome France’s world number 72 Corentin Moutet if he is to make it through to a second-round clash with 19th seed Grigor Dimitrov of Bulgaria.
Speaking about today’s opponent, the Scot said: “I’ve not played against him, but I practised with him once, he’s an unbelievably talented guy.
“He’s not the biggest, he tends to play quite long points but he’s got tons of variety and good hands at the net.
“He can be a bit volatile at times but yeah, a good challenge for me, very different to how most players play in the draw.
“A lot of the game nowadays is based on power and serves and he’s the opposite really. A good test for me.”
04:21 PM BST
Katie Boulter match is under way
Katie Boulter is at 1-2 in the opening set of her first-round match.
Elsewhere, Wimbledon finalist Ons Jabeur has broken in the first game at Louis Armstrong Stadium against Colombia’s Camila Osorio.
Leylah Fernandez, the 2021 US Open finalist who lost to Emma Raducanu, has started on Grandstand.
Meanwhile, Australian Open finalist Alexander Zverev has just got under way against Aleksandar Vukic.
04:09 PM BST
The opening day of Flushing Meadows on Monday saw British qualifier Lily Miyazaki follow in the footsteps of Emma Radacanu to win her first match of the tournament despite having no rank to speak of.
04:02 PM BST
Order of play
Arthur Ashe stadium – from 5pm
(3) Daniil Medvedev (RUS) v Attila Balazs (HUN)
Camila Giorgi (ITA) v (3) Jessica Pegula (USA)
Greet Minnen (BEL) v Venus Williams (USA)
(1) Carlos Alcaraz (SPA) v Dominik Koepfer (GER)
Louis Armstrong Stadium – from 4pm
(5) Ons Jabeur (TUN) v Maria Camila Osorio Serrano (COL)
Arantxa Rus (NED) v (17) Madison Keys (USA)
Facundo Diaz Acosta (ARG) v John Isner (USA)
Yannick Hanfmann (GER) v (6) Jannik Sinner (ITA)
Maryna Zanevska (BEL) v (2) Aryna Sabalenka (BLR)
For more information on the order of play, including all you need to know about the six Britons in action, go here.
03:49 PM BST
Andy Murray: getting over Wimbledon exit took time
Andy Murray admitted he had to go away and lick his wounds after his Wimbledon disappointment.
The Scot was leading world number five Stefanos Tsitsipas 2-1 in their second-round match when the 11pm curfew kicked in.
It seemed the momentum was with Murray but when the match resumed the following day, the two-time champion was beaten in five sets.
Speaking seven weeks on from his Wimbledon exit, Murray revealed it took a few days to get over the narrow defeat, but he quickly set about working on areas of his game which he could improve.
“I went away on holiday straight afterwards,” he said. “Always immediately after matches, especially Wimbledon, at majors there’s greater disappointment and greater emotions than at any other time in the year.
“Probably after three or four days of being away from it, I chatted to my team about things that I feel I need to change, certain shots in my game if I wanted to win more of those matches and dictate more of those matches.
“So I did that, went away and worked on things for a period of time.”
The 33-year-old also slammed Wimbledon’s late matches, which allowed Stitsipas to get back into the game. Click here to read more about Murray’s reaction to his Wimbledon loss.
03:35 PM BST
Six Britons in action
Hello and welcome to Telegraph Sport’s coverage of day two of the US Open.
There are six Britons in action today, with Katie Boulter getting proceedings under way against France’s Diane Parry at 4pm.
She is followed by Andy Murray, who begins his tournament with a first round match against Corentin Moutet of France scheduled for 6.30pm.
It is now 11 years since Murray secured his first grand slam crown at Flushing Meadows. The 36-year-old has shown signs of promise in 2023, reaching the third round of the Australian Open in January and pushing fifth seed Stefanos Tsitsipas close in a five-set loss at Wimbledon.
However, the 33-year-old has been troubled by injury and was forced to withdraw from Cincinnati earlier this month with an abdominal strain. If he overcomes world No 71 Moutet, he is due a tough second-round clash with 19th seed Grigor Dimitrov of Bulgaria.
Cameron Norrie, Dan Evans and Jack Draper also begin their campaigns in the men’s competition today, while Jodie Burrage joins Boulter in the women’s draw.
Norrie has lost four consecutive matches since Wimbledon, while Draper has struggled with a shoulder injury all summer. Evans, meanwhile, endured a difficult run of defeats before winning the biggest title of his career in Washington.
They will all hope to match the form of British qualifier Lily Miyazaki, who won her first main draw Grand Slam singles match on Monday with a scintillating straight-sets victory against Margarita Betova.