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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 3-4 Tiafoe*
Nadal forces deuce as he looks to move on level terms, but Tiafoe once again edges the game out of reach with a cracking ace.
Nadal responds with a defiant forehand down the line, only to see Tiafoe connect beautifully with a cross-court backhand. What a couple of points at the business end of this game!
Nadal 3-4 Tiafoe*
Brave. Frances Tiafoe closes in and rattles a cross-court forehand which skims the line to reach 30-30.
Delightful hitting from the American - the crowd enjoyed that! He hangs on in the rally before fizzing a shot down the line for game point.
Nadal 3-4 Tiafoe*
Rafael Nadal has Frances Tiafoe on the run after a second serve and eventually draws the error from his opponent, who knocks a forehand into the net.
Nadal looking for an immediate response.
Nadal 3-4 Tiafoe*
Can Tiafoe back up that breakthrough to move within touching distance of winning his first ever set against Rafael Nadal?
Big game coming up for the American.
Swiatek 2-6 1-0 Niemeier*
Top seed Iga Swiatek is having to really fight for a place in the quarter-finals on Louis Armstrong Stadium.
The world number one scrapes through her first service game after eight nervy minutes, saving a break point along the way.
Unseeded German Jule Niemeier is taking this match to Swiatek.
Nadal 3-4 Tiafoe*
Laura Robson
Former British number one at Flushing Meadows
This was so disciplined for Tiafoe to hang in the rally and we would not have seen this from him at the start of the year.
Nadal 3-4 Tiafoe*
Another miss from Nadal!
It's advantage Frances Tiafoe in this first set.
*Nadal 3-3 Tiafoe
That's long from Rafael Nadal. Frances Tiafoe will get a break point!
The first of the match. Can he take it? The crowd get behind him before Nadal lines up his serve.
*Nadal 3-3 Tiafoe
Ooh. Fine margins. Tiafoe loses his shot at three break points as a backhand at the net falls wide. The chance of two then disappears. It only takes one, of course...
*Nadal 3-3 Tiafoe
Laura Robson
Former British number one at Flushing Meadows
Frances in the match against Berrettini in Cincinnati came in 29 times and was successful in 22. He has the game for it and he has the touch when he comes forward.
*Nadal 3-3 Tiafoe
Now then. A Rafael Nadal forehand clips the cord and bounces out.
It hands Frances Tiafoe 0-30. A chance.
*Nadal 3-3 Tiafoe
Rafael Nadal isn't happy with himself after a loose forehand brings Tiafoe back into play at 30-30, but a brilliant backhand return brings up a first deuce of the match.
A first deuce - but still no break points!
That Tiafoe serve. Wow. The American holds again.
Nadal 3-2 Tiafoe*
Tiafoe quickly shrugs off a missed volley with a booming ace.
Superb! Nadal whips a forehand down the line - he could not have placed it any better than this - for a 15-30 lead.
Nadal 3-2 Tiafoe*
Laura Robson
Former British number one at Flushing Meadows
We really haven't see too many long rallies yet. That was one of the longest.
Nadal 3-2 Tiafoe*
Nadal produces a first serve to wrap up another hold. Even though he's taken a bit off his serve since his abdominal injury at Wimbledon, the Spaniard is still, so far, delivering the goods.
*Nadal 2-2 Tiafoe
A shake of the fist from Rafael Nadal as he lands his fastest serve of the match so far - a 121mph hit that sees Frances Tiafoe drop his attempt at a return into the net.
He eases to a 40-15 advantage but an overhit groundstroke misses the baseline and brings Tiafoe to within a point...
*Swiatek 2-6 Niemeier
Meanwhile, over on Louis Armstrong, there's a potential upset brewing.
World number one Iga Swiatek has just dropped the first set against world number 108 Jule Niemeier.
A big hitter, Germany's Niemeier broke through at Wimbledon, reaching the quarter finals on her debut at SW19 and taking out second seed Anett Kontaveit on the way.
*Nadal 2-2 Tiafoe
A whopping 135mph ace from Frances Tiafoe. That'll do.
He shakes his racquet in approval as he holds from 30-30. It's heating up nicely.
Nadal 2-1 Tiafoe*
Oh yes! A passing shot and a half from Rafael Nadal. It looks like he's managed to get to the bottom of why he suffered such slow starts in his opening matches.
Back comes Tiafoe with an ace, but there's a groan from the crowd as their man nets for 30-30. Can Nadal create a first opportunity for himself?
Nadal 2-1 Tiafoe*
That's another good hold for Rafael Nadal, as Frances Tiafoe skews a forehand wide. Both players have made decent starts here.