Defending champion Coco Gauff beaten 6-3 4-6 6-3 by Emma Navarro
Britain's Heather Watson knocked out of women's doubles
Grigor Dimitrov sees off Andrey Rublev in five sets to reach men's quarter-finals - report
Home hope Taylor Fritz beats Casper Ruud, with Aryna Sabalenka and Alexander Zverev in action later
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That's your lot for tonight, folks, after another high-profile exit at Flushing Meadows.
Defending champion Coco Gauff is out after defeat by fellow American Emma Navarro.
Thanks for joining us. We'll be back tomorrow when Great Britain's Jack Draper is in fourth-round action against Tomas Machac.
Do join us again for that!
The action is not done yet in New York.
American Frances Tiafoe takes on Novak Djokovic's conqueror Alexei Popyrin very shortly in the evening session on Arthur Ashe.
That's followed by seventh seed Zheng Qinwen of China up against Wimbledon semi-finalist Donna Vekic in the women's singles.
On Louis Armstrong, second seed Aryna Sabalenka faces Belgium's Elise Mertens.
Right then, that's almost it from us tonight but first, let's have a quick look at what has happened so far on day seven at Flushing Meadows...
Navarro 6-3 4-6 6-3 Gauff
At 23, Emma Navarro is the youngest American player to make the quarter-finals at both Wimbledon and the US Open in the same year since Serena Williams in 2004.
She is also the first American to defeat the defending women's champion at the US Open since Williams beat her sister Venus in the 2002 final.
Navarro 6-3 4-6 6-3 Gauff
Emma Navarro on beating the defending champion Coco Gauff to reach her first US Open quarter-final: "It's pretty insane. I lost in the first round the last two years and now to be making the quarter-finals is pretty insane.
"This is the city I was born in and it feels so special to be playing here. Coco [Gauff] is an amazing player. I have a ton of respect for her and I know she's going to come back here and win this thing again."
On how she regrouped to win the third set: "It was tough losing the second set. I was able to regroup after the second set and come into the third set with a fresh mindset. I wanted to play aggressive tennis and I think I was able to do that."
Image source, Getty ImagesNavarro 6-3 4-6 6-3 Gauff
Emma Navarro is through to the quarter-finals at Flushing Meadows for the first time.
It's just her second time in the last eight at a Grand Slam after reaching the same stage at Wimbledon earlier this year.
The stats don't make great reading for Coco Gauff, though.
She had 60 unforced errors to go with those 19 doubles faults - and just 14 winners.
Navarro won't be too pleased with her 35 unforced errors to 20 winners but she will be delighted with the win.
Navarro 6-3 4-6 6-3 Gauff
Emma Navarro ends Coco Gauff's reign as US Open champion!
It was a real struggle for Gauff, particularly on serve at times, but what a moment for Navarro.
Her first match on Arthur Ashe - she had a wobble in the second set when she was closing in on victory but regrouped to claim a memorable win.
Image source, Getty Images*Navarro 6-3 4-6 5-3 Gauff
A third double fault in the game takes Coco Gauff's tally up to 19 and it's match point Emma Navarro...
*Navarro 6-3 4-6 5-3 Gauff
Ryan Harrison
Former American tennis player on BBC Radio 5 Live and BBC Sounds
Not too many mistakes off the backhand of Emma Navarro today. If she has made a mistake, it's more likely to be on the forehand side.
Image source, Getty Images*Navarro 6-3 4-6 5-3 Gauff
The youngsters watching have decided the game is up for Coco Gauff.
They're running down to be in prime position for autographs after the match, leading to a slight delay.
Gauff is ready to serve now, though.
Navarro 6-3 4-6 5-3 Gauff*
How on earth did Emma Navarro win that point?
A poor drop shot gives Coco Gauff a chance to go up 0-30 but Navarro scraps and scrambles to stay in the point before the third seed nets a forehand.
That could be crucial. Navarro then produces a wonderful backhand winner to bring up two game points and takes it on the second.
Navarro will serve for the match - unless she can break Gauff again and save herself the stress...
Nakashima 6-3 1-6 0-2 Zverev*
Alexander Zverev has won eight of the last nine games in his fourth-round match against American Brandon Nakashima.
The fourth seed is now ahead in the third set on Louis Armstrong Stadium.
Navarro 6-3 4-6 4-3 Gauff*
Back-to-back double faults for Coco Gauff see 30-0 become 30-30 and give Emma Navarro an opportunity.
A forehand balloons off the frame of Navarro's racquet to make it 40-30 but another double fault from Gauff takes it to deuce.
Yet again, though, Gauff muddles her way through to a vital hold.
Image source, Getty ImagesNavarro 6-3 4-6 4-2 Gauff*
Big hold for Emma Navarro to maintain her advantage.
There were a couple of cracking shots from the 13th seed, a whipped backhand cross-court past Coco Gauff the pick of them.
Navarro seems calm for now but it was about this stage of the second set that she began to wobble. Can she see it through this time?
*Navarro 6-3 4-6 3-2 Gauff
Annabel Croft
Former British number one on BBC Radio 5 Sports Extra and BBC Sounds
What a final point that was. Absolutely breathtaking ball-striking from both of them, using the full court, going toe-to-toe with the power, the pace and the accuracy and it was Coco Gauff who came out on top.
She never looked like losing that point, digging in there. Very, very impressive.
*Navarro 6-3 4-6 3-2 Gauff
Coco Gauff hammers a forehand into the corner to secure the hold.
At 15-30, she was up against it but she followed up a double fault with an ace and took it from there.
The crowd are still right behind her but Emma Navarro remains a break up in this deciding set.
Image source, Getty Images*Nakashima 6-3 1-6 0-0 Zverev
It's all square in the other fourth-round singles match happening right now as fourth seed Alexander Zverev wins the second set against American Brandon Nakashima.
The winner of this match will face 12th seed Taylor Fritz for a place in the semi-finals.
Navarro 6-3 4-6 3-1 Gauff*
Ryan Harrison
Former American tennis player on BBC Radio 5 Live and BBC Sounds
Coco Gauff all through this tournament has done a great job of not necessarily passing the eye test but still finding a way to make her way through these matches that have been so difficult for her to manage.
If she can continue to keep this close then maybe, just maybe, Emma Navarro will blink again.
Navarro 6-3 4-6 3-1 Gauff*
Emma Navarro looks to have shaken off the disappointment of letting that second set slip.
She's back in her groove and seals the hold with a fantastic reach to make Coco Gauff play the overhead on the stretch.
Gauff netted it and Navarro has a two-game buffer. Break consolidated.
Image source, Getty Images*Navarro 6-3 4-6 2-1 Gauff
Oh dear. Double faults have been costly for Coco Gauff today but perhaps never quite as costly as this game.
Having saved two break points, the second of which came because of a double fault, the defending champion double-faults twice in a row to hand Emma Navarro the break.
That's 12 in the match for Gauff and she's a break down in the deciding set.