Day one of the US Open in New York - listen to live commentary on BBC 5 Sports Extra (UK only)
Katie Boulter beats American wildcard Carol Young Suh Lee 6-4 3-6 6-0 to reach second round
Qualifier Toby Samuel earlier saw off Tomas Machac 6-2 6-3 6-2 on New York debut for first Grand Slam match win
But 29th seed Cameron Norrie lost 6-7 (6-8) 6-2 6-2 6-3 to Luca Van Assche
Third seed Jessica Pegula breezes through, 2021 champion Daniil Medvedev wins on Arthur Ashe Stadium
Novak Djokovic and Venus Williams in action in night session
Samuel 6-2 6-3 0-2 Machac*
Well, well. I didn't see that coming. With a backhand volley, Tomas Machac converts his third break point opportunity to lead 2-0 early in the third set. Toby Samuel was near untouchable on serve in the previous two sets...
Norrie 7-6 (8-6) 2-6 2-6 1-1 Van Assche*
Luca Van Assche has never won a match at the US Open, with this the 22-year-old's second appearance in the main draw in New York.
He will be feeling extremely confident of achieving that first win here.
But Cameron Norrie settles in to this must-win fourth set with a comfortable hold.
*Samuel 6-2 6-3 0-1 Machac
Tomas Machac wastes his two break points with a pair of errors but nails a smash winner on deuce. Third time lucky?
Image source, Getty Images*Norrie 7-6 (8-6) 2-6 2-6 0-1 Van Assche
Pat Cash
Former Wimbledon champion on BBC Radio 5 Live
Three absolute marathon rallies in that game.
Norrie clearly changed the game plan and he hadn't won any of those points yet which was discouraging, but he certainly signalled to Van Assche that if you're going to win this match, I'm going to make you earn it.
Medvedev 6-4 6-2 6-4 Gaston
An impressive performance by Daniil Medvedev as he wraps up a composed victory over Hugo Gaston with a straightforward hold to love.
That win has got to give the former US Open champion a lot of confidence heading into the second round. It doesn't get much easier than that.
He'll face American Sebastian Gorzny, the world number 731, or Belgium's Raphael Collignon next.
Image source, Getty Images*Samuel 6-2 6-3 0-1 Machac
Toby Samuel LOSES his opening point on serve in the third set, putting a forehand long.
A backhand sprayed into the tramlines for 15-30 adds to the untidiness and then... a netted backhand.
Huge moments for Tomas Machac.
*Norrie 7-6 (8-6) 2-6 2-6 0-1 Van Assche
That is such an impressive game from Luca Van Assche. Some brilliant points and winners, and he polishes it off with an ace.
Cameron Norrie didn't do much wrong there, he was just outplayed.
*Samuel 6-2 6-3 0-1 Machac
Two forehand errors from Tomas Machac - the second wild and long - give up 0-30 in the opening game of the third set.
The Czech recovers to 30-all, getting on top of the baseline and forcing errors from Toby Samuel in lengthy baseline exchanges, and makes it four points in a row as he completes the hold.
Norrie 7-6 (8-6) 2-6 2-6 0-0 Van Assche*
The fourth set begins with a 29-shot rally and, in keeping with the past two sets, it is Luca Van Assche who conjures up the winner.
A brilliant backhand delights the crowd.
Wow, another 29-shot rally on the second point, and again Van Assche outlasts his opponent. This has got to be really dispiriting for Norrie, there's just no way through at the moment.
Norrie 7-6 (8-6) 2-6 2-6 0-0 Van Assche*
There hasn't been anything obviously wrong physically with Cameron Norrie.
But he has not been able to maintain the level he showed in the first set, while Luca Van Assche has moved up a gear or two since then.
After taking the third set on Norrie's serve, Van Assche will once again get to serve first in what he will seek to make the final set of this contest.
Image source, Getty ImagesSamuel 6-2 6-3 0-0 Machac*
Toby Samuel's serve has been his biggest weapon in this match so far.
Although his first-serve percentage is only 62%, he's won 24/26 points behind it. He's won 81% points on his second serve.
Machac also hasn't helped himself, hitting 17 unforced errors to Samuel's six.
Norrie 7-6 (8-6) 2-6 2-6 0-0 Van Assche*
Pat Cash
Former Wimbledon champion on BBC Radio 5 Live
Norrie isn't 100% for sure. Whether it's his form, or physically, whatever it happens to be, maybe his confidence.
It's not a great scoreline and it indicates something is wrong. He's shaking his head and having a chat with his team. Things are definitely not going well.
Norrie 7-6 (8-6) 2-6 2-6 0-0 Van Assche*
Another unforced error from Cameron Norrie hands Luca Van Assche two set points, and he concedes it with his third off the forehand wing in this game alone.
It's one-way traffic right now, and Norrie is going to have to do this the hard way if he is to make it into the second round in New York.
The body language isn't great as he heads to his chair after missing a final volley.
Image source, Getty ImagesSamuel 6-2 6-3 0-0 Machac*
Toby Samuel comes on the approach and buries the forehand winner. He's one set away from his first Grand Slam main-draw win.
Image source, Getty Images*Samuel 6-2 5-3 Machac
Toby Samuel offers a celebratory clenched fist as he hammers home a down-the-line forehand for 15-0. That might be the first emotion he's shown across these opening two sets.
He quickly navigates the next two points to lead 40-0. Three more set points.
*Samuel 6-2 5-3 Machac
Tomas Machac saves a second set point, getting Toby Samuel on the run and burying a forehand into the corner of the court, and comes through the hold.
Samuel will serve for the second set.
*Norrie 7-6 (8-6) 2-6 2-5 Van Assche
There's not much Cam Norrie can do about a 132 mile-per-hour ace as Luca Van Assche begins his next service game.
But the Briton is visibly disappointed after being caught out by a lob.
Another bit of magic from Van Assche, who curls in a backhand winner from deep, helps take him one game from the third set.
Samuel 6-2 5-2 Machac*
But he'll have a second bite, stretching Tomas Machac across the baseline and being rewarded with a netted forehand.
*Medvedev 6-4 6-2 4-3 Gaston
Hugo Gaston is just about keeping himself in this first-round match on Arthur Ashe Stadium.
He's been taken to deuce in his last three service games by Daniil Medvedev, but somehow he's managed to hang in there and avoid falling a double break down.
Samuel 6-2 5-2 Machac*
Toby Samuel rocks his head back after netting a routine forehand. Set point comes and goes.
