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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
*Nadal 4-6 6-4 3-3 Tiafoe
Tiafoe opens up as he goes for the kill only to see his forehand nestle into the net, but Nadal misses a routine forehand and there's some danger for the world number three here at 30-30.
*Nadal 4-6 6-4 3-3 Tiafoe
Both players are pushing the boundaries with their shots, but this time it's Nadal who just makes a serve before Tiafoe narrowly misses the line on a return.
A double fault from Nadal - his fourth - brings Tiafoe into play.
*Nadal 4-6 6-4 3-3 Tiafoe
Nadal just can't get the extra bit of power needed behind a backhand as he misses the chance for 0-30.
A wayward slice wide from the Spaniard hands Tiafoe the initiative and, after the American nicks the line from the baseline, he holds with a blistering ace for 3-3.
Nadal 4-6 6-4 3-2 Tiafoe*
So, who will blink first in set three?
It's been a match of fine margins on Arthur Ashe. Back over to Frances Tiafoe.
Nadal 4-6 6-4 3-2 Tiafoe*
An ace followed by a double fault from Nadal. Such is life.
No bother, though. The Spaniard is still hitting big on serve despite those first set concerns, polishing off a hold to 15 with a punchy forehand into the corner.
*Nadal 4-6 6-4 2-2 Tiafoe
Laura Robson
Former British number one at Flushing Meadows
It is going much like the second set. easy holds until we get to 4-4 but for me Frances looks a little more tired now.
He is trying to focus on the tennis but Nadal is finally finding some form and looking much better than at the start of the match.
*Nadal 4-6 6-4 2-2 Tiafoe
Both players have been holding their own with few problems on serve, but Nadal does manage to reach 40-30 in this latest game before Tiafoe can put it to bed.
Tiafoe appeared to set the tone for another comfortable game with an ace, but a crowd-pleasing forehand winner from Nadal almost saw him fight back.
*Swiatek 2-6 6-4 6-0 Niemeier
Iga Swiatek, who was down a set and a break, somehow comes away with a win over unseeded Jule Niemeier to reach the quarter-final.
She hung in there and now the French Open champion is three matches away from a first US Open title.
The world number one will now face American eighth seed Jessica Pegula in two days time.
Nadal 4-6 6-4 2-1 Tiafoe*
Nicely done once again from Rafael Nadal. A forehand winner completes another hold - though to 15 this time - as he keeps his nose in front in the early stages of the set.
*Swiatek 2-6 6-4 5-0 Niemeier
Iga Swiatek squeezes through a service game to go 5-0 up in the decider.
She now has a chance to serve for the match and take a 19th set 6-0 this season.
*Nadal 4-6 6-4 1-1 Tiafoe
Anything you can do...
Frances Tiafoe responds with a fine service game of his own and races into a 40-0 lead. A clean forehand - and a clean game from Tiafoe, who brushes off that costly double fault at the end of the second set.
Nadal 4-6 6-4 1-0 Tiafoe*
A solid start to set three from Rafael Nadal. An ace sets him away to a love hold. Very comfortable.
*Nadal 4-6 6-4 0-0 Tiafoe
After two sets, and one hour and 46 minutes of action on Arthur Ashe, the players are tied on 58 apiece for points won.
More of the same, please! It's been a great match-up so far.
Purcell/Ebden 6-7 (5-7) 6-3 Koolhof/Skupski
In the men's doubles on court five Brit Neal Skupski and Dutchman Wesley Koolhof have just conceded the second set to Australian pairing, Matthew Ebden and Max Purcell.
The second seeds go to a decider against the pair who won the Wimbledon title in July.
*Swiatek 2-6 6-4 4-0 Niemeier
Iga Swiatek goes two breaks up in the final set.
She had an almighty scare on Louis Armstrong Stadium today but it looks as if she's about to get over the line against unseeded Jule Niemeier.
*Nadal 4-6 6-4 0-0 Tiafoe
Laura Robson
Former British number one at Flushing Meadows
There is so much more of a dialogue with Nadal and his box, going back and forth and maybe disagreeing with them, because they constantly look baffled as he walks away.
*Nadal 4-6 6-4 0-0 Tiafoe
Oh no - a double fault from Frances Tiafoe and we're all level on Arthur Ashe!
Nadal, with his first break points of the match, strikes when it counts to take the second set 6-4 on the American's serve.
Game on!
Image source, Getty ImagesNadal 4-6 5-4 Tiafoe*
Great defensive work by Rafael Nadal but Frances Tiafoe continues to apply pressure before saving the first set point with a great backhand.
Nadal 4-6 5-4 Tiafoe*
Back-to-back looks of disbelief from Frances Tiafoe.
The American misses with a backhand by the smallest of margins, before Rafael Nadal catches a stunning cross-court forehand on the stretch and somehow just manages to scorch the line.
Trouble for Tiafoe? Trouble for Tiafoe! Two set points for Nadal.
Nadal 4-6 5-4 Tiafoe*
A last-minute change up from Nadal, who decides to shuffle back for Tiafoe's first serve - but the American just sends an ace flying down the middle anyway.