Use audio icon at top of page to listen BBC Radio 5 Sports Extra commentary (UK only)
Rafael Nadal beaten by Frances Tiafoe 6-4, 4-6, 6-4, 6-3
World number one Iga Swiatek beats Jule Niemeier 2-6 6-4 6-0
Swiatek will play Jessica Pegula who defeated Petra Kvitova 6-3 6-2
Cameron Norrie loses 6-4 6-4 6-4 to Andrey Rublev in last 16
Collins v Sabalenka followed by Cilic v Alcaraz in night session (midnight UK)
Day eight of final Grand Slam of year at Flushing Meadows
*Pegula 1-0 Kvitova
American eighth seed Jessica Pegula's match with two-time Wimbledon winner Petra Kvitova has just got under way on Arthur Ashe Stadium.
Pegula is in the last 16 of the US Open for the first time but she's not feeling any pressure so far, as she immediately breaks her experienced opponent.
Norrie 4-6 2-3 Rublev*
There are some spots of rain on the court...
Rublev, meanwhile, is having a lengthy complain to the umpire about what I suspect will be the roof closing. It means the humidity will go up massively inside the stadium.
Jonathan Jurejko
BBC Sport at Flushing Meadows
The court is still bathed in sunshine. But dark clouds are gathering overhead.
Feels like the players might get a drenching like Truman Burbank any minute.
Norrie 4-6 2-3 Rublev*
I think it's raining...
Norrie 4-6 2-3 Rublev*
It's still not quite clicking for Norrie - I haven't seen him make this many errors in some time - but he does well enough on a one-two punch to hold to 30 and stop the run of games for Rublev.
Jonathan Jurejko
BBC Sport at Flushing Meadows
Image source, BBC SportAs discussed earlier, there is a healthy holiday crowd on Louis Armstrong Stadium today.
One of the fullest I've seen the upper tier in the 14,000-seater arena.
And yes, the second show-court in New York is named after that Louis Armstrong.
Not because the jazz musician could tinkle a tune out of a racquet, more that Satchmo grew up across the tracks in Flushing.
Norrie will be hoping he has all the time in the world to turn this match around.
*Norrie 4-6 1-3 Rublev
Naomi Broady
British player on BBC Radio 5 Sports Extra
That is why Cam is avoiding that forehand of Rublev.
*Norrie 4-6 1-3 Rublev
Brilliant defence from Rublev, stretching all over the show at the back of the court, and he's able to blast a forehand back quick enough to outmuscle Norrie, who nets.
That's an excellent hold from Rublev, who holds courtesy of a long Norrie return.
Norrie 4-6 1-2 Rublev*
Norrie has Rublev right where he wants him, stranded at the net, but he sends his passing backhand long!
Advantage, Rublev... but he can't take it, a low, swirling backhand bobbling over the tramlines for another deuce.
Tim Henman, meanwhile, informs us that it looks like its about to rain.
Norrie 4-6 1-2 Rublev*
Only just!
Rublev takes an overhead and almost spanks the ball out of bounds, but it comes down just inside the baseline to take us back to deuce.
Norrie 4-6 1-2 Rublev*
Now then...
Rublev double faults and it's break point Norrie, who gets a huge cheer from the crowd.
Norrie 4-6 1-2 Rublev*
Down comes another huge serve from Rublev, giving him the advantage, but a backhand floats into the net tape to give Norrie another brief glimmer.
Norrie 4-6 1-2 Rublev*
Can Rublev back up the break?
An ace gets him off to a nice start but a long forehand gives Norrie a glint at 30-30, before the Brit spears another backhand over the tramlines. It just hasn't worked for him today so far.
Mind you, that's a thumping forehand from Norrie, skipping past Rublev to force deuce.
Norrie 4-6 1-2 Rublev*
David Law
Commentator on BBC Radio 5 Live
What is going on? Norrie hasn't got the rhythm. He can't find a first serve either. These are slightly concerning times for him - nothing is working for him at the moment.
It is like his string tension is wrong because the ball is just flying.
Norrie 4-6 1-2 Rublev*
That's a poor, un-Norrielike forehand that goes flying past Rublev, and it gifts him a break.
*Norrie 4-6 1-1 Rublev
Norrie, who does not look happy, misses a first serve, but gets away with a second that Rublev sends just over the baseline.
30-40. Still another chance for Rublev.
*Norrie 4-6 1-1 Rublev
Norrie's backhand is just not clicking, and now his forehand goes awry to help Rublev creep onto his serve at 15-30.
That's a big shot from Rublev, though, and a long Norrie forehand gives Rublev two break points.
*Norrie 4-6 1-1 Rublev
Cam Norrie gets himself into a fine position for a backhand winner and ends up spearing it long.
Another error off the same wing hands Rublev game point and Norrie goes too big on a return of serve to help his opponent along to a hold.
Norrie casts an annoyed glance up at his box before he resets himself to serve.
Norrie 4-6 1-0 Rublev*
David Law
Commentator on BBC Radio 5 Live
There's no panic from Norrie - he's been here many times before, but the one caution I would have was what happened at the French Open where he went two sets down against Karen Khachanov and he just couldn't reel him in.
He can't let Rublev do the same thing.
Norrie 4-6 1-0 Rublev*
A deeply irked Rublev larrups long to give Norrie game point, and a big serve down the T isn't returned cleanly by Rublev.
Norrie, under some pressure, holds.