NADAL 5-7 7-5 7-6(7) 7-6(6) KHACHANOV: Nadal's experience tells in the tie-break, setting up five match points; he loses the first with a net, loses the second thanks to a brilliantly-placed shot from Khachanov, but takes the third when the Russian misses his return. Almost four and a half hours on court. What an epic.
Rafael Nadal - Karen Khachanov
US Open men - 31 August 2018
US Open – Follow the Tennis match between Rafael Nadal and Karen Khachanov live with Eurosport. The match starts at 17:00 on 31 August 2018. Our live coverage lets you follow all the key moments as they happen.
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NADAL 5-7 7-5 7-6(7) 6-6 KHACHANOV: Well, that's one way to set up a tie-break - Khachanov hits a tweener, and Nadal meets it at the net with a backhand laden with top spin.
NADAL 5-7 7-5 7-6(7) 5-6 KHACHANOV: Khachanov is hitting his calves with his racquet, and it seems to be having an effect. He's moving better now, and the crowd are getting behind him.
NADAL 5-7 7-5 7-6(7) 5-5 KHACHANOV: An incredible backhand as Khachanov breaks to love! Nadal's making mistakes, hitting a terrible volley, and this match goes on.
Nadal to serve for the match, then.
NADAL 5-7 7-5 7-6(7) 5-4 KHACHANOV: More great use of shots from Khachanov on his serve, using the backhand delicately to dip over the net.
NADAL 5-7 7-5 7-6(7) 5-3 KHACHANOV: The Nadal forehand is firing as the clock ticks nearer to the four-hour mark.
NADAL 5-7 7-5 7-6(7) 4-3 KHACHANOV: Another hold to love on the Khachanov serve! So tenacious. And another ace to wrap up the game to boot.
NADAL 5-7 7-5 7-6(7) 4-2 KHACHANOV: Khachanov tries his hand at challenging in this game, perhaps rather more in hope than expectation.
NADAL 5-7 7-5 7-6(7) 3-2 KHACHANOV: But the Russian isn't done quite yet. He keeps hold of his serve but does he have enough left to make inroads on Nadal's?
NADAL 5-7 7-5 7-6(7) 3-1 KHACHANOV: That's the shot of a tired man. Khachanov isn't keeping up with the stamina of Nadal now.
NADAL 5-7 7-5 7-6(7) 2-1 KHACHANOV: The Nadal backhand comes into play to break Khachanov, who must be flagging a bit.
NADAL 5-7 7-5 7-6(7) 1-1 KHACHANOV: Nadal holds too, and there's a certain amount of tension around Ashe. Khachanov is starting to grunt a bit on each shot - how much does he have left?
NADAL 5-7 7-5 7-6(7) 0-1 KHACHANOV: Here we go with the fourth, then, and Khachanov gets on the board first up on his serve.
NADAL 5-7 7-5 7-6(7) KHACHANOV: Nadal is 6-3 up in the breaker but allows Khachanov back in again - he needs his fifth set point to finally wrap this up, putting more pace on the ball and leaving the Russian to return into the net.
NADAL 5-7 7-5 6-6 KHACHANOV: Another ace to wrap up a hold to love, and we're into a tie-break.
NADAL 5-7 7-5 6-5 KHACHANOV: A subdued fist-pump for Nadal, who's picking up the pace on his return shots.
NADAL 5-7 7-5 5-5 KHACHANOV: Not quite yet. Khachanov adds a 16th ace to his tally and takes the game to love.
NADAL 5-7 7-5 5-4 KHACHANOV: Now then. Can the defending champion brerak the Khachanov serve to take this tight third set?
NADAL 5-7 7-5 4-4 KHACHANOV: Nadal has a little grimace as he bounces and leans slightly on that sore knee. Khachanov holds serve.
NADAL 5-7 7-5 4-3 KHACHANOV: A hold to love for Nadal, who shows off an incredible inside-out forehand.
NADAL 5-7 7-5 3-3 KHACHANOV: Khachanov is allowing so many mistakes creep into his game, missing a backhand, challenging a call that was well out, but Nadal can't get rid of him that easily.
NADAL 5-7 7-5 3-2 KHACHANOV: Khachanov hits a brilliant winner down the line, but Nadal is skidding into the net much more aggressively now.
NADAL 5-7 7-5 2-2 KHACHANOV: Khachanov is dogged here, but a re-energised Nadal looks more likely to make the most of any opportunities than he did an hour ago.
NADAL 5-7 7-5 2-1 KHACHANOV: Almost two and a half hours gone now as the players head to their chairs. Nadal is moving very friskily.
NADAL 5-7 7-5 1-1 KHACHANOV: Khachanov will be pleased to be on the board first off in this third set. He's still hitting powerfully but looks a little more nervous than he did two hours ago.
NADAL 5-7 7-5 1-0 KHACHANOV: Nadal comes back from love-40 down to hold his serve against the sheer strength of Khachanov.
NADAL 5-7 7-5 KHACHANOV: Khachanov double-faults on game point. And then does it again. His second serve is looking shaky and Nadal gobbles up that set point.
NADAL 5-7 6-5 KHACHANOV: Nadal is raring to go after that brief break for the roof to close. He takes his seat at the end of the game and gets his knee re-taped - the taping is just below his right knee-cap.
It's raining! Roof is about to close again.
NADAL 5-7 5-5 KHACHANOV: Screaming and whistling as Nadal digs very deep to break Khachanov. The Russian is still looking very powerful, and the top seed is playing far too much to his forehand.
NADAL 5-7 4-5 KHACHANOV: Nadal cannot believe he's let this service game slip. He misses a straightforward forehand, and Khachanov has broken him right back.
NADAL 5-7 4-4 KHACHANOV: Back on serve! Nadal targets the second serve, returning with a little more height, and he gets the break back.
NADAL 5-7 3-4 KHACHANOV: Nadal's also quick to send his racquets off court to get re-strung during this changeover. He's a man of routine, he'll want his tools back.
NADAL 5-7 2-4 KHACHANOV: Hold of serve for the 27th seed, and there's a very odd vibe around the Ashe stands as the defending champion is being met punch for punch.
NADAL 5-7 2-3 KHACHANOV: Nadal's coach Carlos Moya has his arms folded in the stands; his charge heads back to his seat and begins to rearrange his drinks bottles.
NADAL 5-7 1-3 KHACHANOV: Nadal has two break point but cannot capitalise - he's standing well back from the baseline and Khachanov is showing so much firepower.
NADAL 5-7 1-2 KHACHANOV: And that's a break to love for Karen Khachanov! Nadal is looking at his camp with a little shrug - could it be a bigger problem with his right knee than that small amount of tape is indicating?
NADAL 5-7 1-1 KHACHANOV: Nadal's looking a little rattled here - he can't capitalise on a 15-30 lead to break the Khachanov serve.
NADAL 5-7 1-0 KHACHANOV: Nadal is turning up the volume as he hits his shots but it's not helping him increase the speed of his forehand - 4mph slower than his opponent's.
NADAL 5-7 KHACHANOV: What a terrific game of tennis! Nadal doesn't want to be shrugged off, and keeps clawing back set point, but Khachanov will not be denied.
NADAL 5-6 KHACHANOV: A magnificent passing shot down the line from Khachanov, taking up Nadal's loose volley to secure a second break of serve.
NADAL 5-5 KHACHANOV: Blistering hold to love for Khachanov, and a very happy fan in the stand who's caught a stray ball.
NADAL 5-4 KHACHANOV: Great serving from Nadal, tempting Khachanov into mistakes and hitting into the net.
NADAL 4-4 KHACHANOV: Khachanov misses his first serve on break point, and Nadal using that forehand to send the winner across and get that break back.
NADAL 3-4 KHACHANOV: Lovely volleying from Nadal to hold his serve under pressure.
NADAL 2-4 KHACHANOV: Eighteen out of 20 first serves for Khachanov so far. That's an incredible stat.
NADAL 2-3 KHACHANOV: Good, fiery stuff from Nadal, moving into the net and increasing his winner count. He knows Khachanov could be tricky.
NADAL 1-3 KHACHANOV: A hold to love as Khachanov mixes up aces and winners.
NADAL 1-2 KHACHANOV: Brilliant from young Khachanov, and Nadal is already getting cross. His second serve isn't good - is the serve clock putting the pressure on?
NADAL 1-1 KHACHANOV: Nadal's forehand down the line is so epic it even destroys a courtside microphone on its journey. Khachanov does really well to recover from that and hold.
NADAL 1-0 KHACHANOV: Some huge hitting from these two to get us off and running.
Nadal to serve.
The roof is open again on Ashe.
Rafael Nadal and Karen Khachanov are next in action on Arthur Ashe Stadium.