Live Commentary: Andy Murray vs. Stanislas Wawrinka - as it happened

Hello, and welcome to Sports Mole's live coverage of the US Open quarter-final clash between Andy Murray and Stanislas Wawrinka.

Well what a quarter-final we could have in store for us tonight. Murray is the defending champion at Flushing Meadows, but he will have to perform at his very best to overcome a rejuvenated Stanislas Wawrinka, who is playing some of the best tennis of his career.

The two players are currently making their way onto court at the Arthur Ashe Stadium, so that should mean we are around 10 minutes away from getting underway.

The crowd in New York are currently catching their breath after an epic three-set doubles match. The Bryan brothers had been hoping to secure their fourth major of the year, but despite taking the opening set, they succumbed to an excellent fightback from Radek Stepanek and Leander Paes.

This meeting will be Murray and Wawrinka's third at the US Open. The Scot dropped just seven games in winning their first encounter, but the Swiss number two rallied from a set down to beat Murray in 2010.

It will be Wawrinka to serve first. Strap yourself in - this could be a classic.

Good start from Wawrinka, who forces Murray to go long twice in succession. However, after Wawrinka goes wide, Murray plays a immaculate lob over his opponent for 30-30. He plays an even better one on the next point, but he nets on the follow up, before repeating that effort to concede the game.

Wawrinka over-hits a baseline shot on the opening point, before Murray survives some brutal backhand hitting from Wawrinka on the next to put away a volley. The Swiss strikes back with some heavy shots, but Murray responds in kind, moving to two game points. It's a tame end to the game for Wawrinka, who hits a forehand into the net.

The players share the opening points, before Wawrinka registers the first ace of the match. Murray nets on the next, and the Swiss seals the game after ghosting into the net to convert a volley.

The rhythm of the match isn't being helped by the wind, and it causes Murray to float a forehand wide, but it is a similar occurrence on the next, this time Wawrinka missing with a backhand. Wawrinka makes two errors either side of a booming forehand to gift Murray game point, but it's saved with a smash down the line. Wawrinka's power off the ground looks huge, and it helps take the game to a third deuce. The players are finding themselves involved in some engaging rallies, but it's Murray who holds for 2-2.

The world number 10 coasts into a 40-0 lead, before conceding a double fault. He manages to outwit Murray on the next point though, being left with the simple task of hitting a forehand into the open court.

Murray could do with a comfortable service-hold, and he looks on course with a 30-0 lead. However, a sloppy backhand volley into the net lets Wawrinka back into the game, but he replies with an ace down the middle. Wawrinka hits back for deuce, partly thanks to another baseline winner, but Murray digs in to hold for a third time.

What happened there? Wawrinka attempts to rip a backhand down the line but he completely misses the ball. A huge ace makes up for the error, but another glaring miss, this time from a volley, gives Murray 15-30. That's as good as it gets for Murray, who floats a return wide after two big serves had given him game point.

Wawrinka creates an opening, but he can only dump a volley into the net. The wind is continuing to play havoc, with both players committing as the game reaches 30-30. Crucial time for the Scot, but he smashes an ace down the middle, before a second heavy serve sees Wawrinka net.

Murray is finding it difficult to get into his opponent's service games, and it is the same story here, with a 136mph ace taking Wawrinka to game point. However, Murray fights back and he gets to deuce when Wawrinka frames a backhand. Bu the Scot misses out after another Wawrinka miss-hit, and the Swiss player takes the game with a drilled forehand that finds the corner.

BREAK AND SET! Murray benefits from a net cord on the opening point, but Wawrinka's power is out on display once more to get him to 15-15. The world number then concedes a double fault and Murray is in trouble at 15-30. An outstanding points brings it back to 30-30, but Wawrinka has set point when Murray nets. WHAT A SERVE! Murray thumps down a huge serve out wide to bring up deuce, but it is set point again after another forehand error. The tension is growing, and despite Wawrinka dictating the point, Murray plays a fine defensive backhand to force the mistake. A THIRD forehand error from Murray concedes another set point, but again, he saves, this time with a drive volley. This is an incredible game, and it's Murray's turn to miss out on game point. WOW! Murray's looks to have played the perfect serve-and-volley but Wawrinka stretches to send a backhand passing shot down the line. Fourth set point, but Wawrinka goes long! What an exhausting game, and Murray plays a superb slice backhand on the run to force a volley mistake. Wawrinka frames a backhand after a 17-shot rally, but Wawrinka replies with a return winner. Even I need a sit down after this. DOUBLE FAULT! Murray sends a second serve long and it's another set point to Wawrinka, but it is SAVED, AGAIN! Wawrinka goes wide with the backhand pass. SIXTH SET POINT as Wawrinka rockets a forehand winner into the corner. This time, after a 16-minute game, Wawrinka takes the set after Murray goes long. That was a huge game.

That was an incredible game of tennis. Not quite the last game in a Wimbledon final, but it could be up there in terms of the direction that this match will now take.

As expected, Wawrinka is out for this second set fired-up, where Murray looks, well, worn out. A love service-hold for the Swiss and Murray's back is firmly against the wall. He must hold this next service game.

Super start from the Scot, who fires down an ace before an perfectly-timed drop-shot takes him to 30-0. Wawrinka attempts one of his own, but it drops into the net. However, a double fault and a passing shot get Wawrinka to 40-30, and a second serve gets the treatment that it deserves for deuce. Murray is well below-par, and he falls break point behind when he goes long with a lob. A SECOND SERVE ACE! Murray survives, and he finds the corner with a first serve to bring up another game point. Wow, Murray needed that hold, and he has got it, with a return going long.

Wawrinka powers his way to 30-0, before Murray halts him in his tracks with a backhand lob. Wawrinka then goes long with a forehand, and out of nowhere, Murray has 30-30. Murray has yet to create a break point, and it's the same story here after a Wawrinka smash. It's another game to Wawrinka, after Murray fails with another attempt at a lob.

Wawrinka is holding nothing back in the power stakes! He nearly obliterates the net with a forehand for 30-15, but he smashes a return winner for 30-30. That's excellent from Murray, who hits a backhand volley onto the baseline, before sealing the game with a thunderous forehand from inside the court.

Murray draws Wawrinka into the net to win the first point, but the Swiss comes out on top with some neat play at the net. Murray's getting no luck on the Wawrinka serve though, and after dictating a lengthy exchange, the Swiss strikes with a superb backhand winner. Game to the world number 10.

BREAK! Uh oh! Murray dumps the first point into the net, before doing the same with a simple backhand volley at the net. 0-30 soon becomes 0-40 after he rushes an approach shot. Three break points to Wawrinka, and he takes it on the first after letting loose with a backhand. This isn't looking good for the defending champion.

There's simply no range or rhythm with Murray's shots. He is getting beaten to the punch, and Wawrinka doesn't look like wilting. An ace takes the Swiss to game point, and it's 10 points in a row for the world number 10, who moves to within one of the second set.

Wawrinka's hitting has been ridiculous at times, and it's on show again when he smashes a flat forehand past the Scot. Murray gets back to 30-30 when Wawrinka nets, but the game moves to deuce after Murray sends a forehand marginally wide. Murray eventually holds, but he is clinging onto this set by a thread. He must break here.

SET! Murray forces Wawrinka into a mistake after a lengthy rally, but an extremely sloppy backhand allows Wawrinka back into the game. The Swiss number two just looks too good at the moment, but a net cord helps Murray back in at 30-30. Wawrinka catches the line with a first serve and it's set point to Wawrinka, which he takes when Murray sends a return wide. The anguish from Murray is for all to see...and hear.

Wawrinka's play has been brutal, and another sensational hit earns him 0-15. Murray fights back for 40-15, but a sublime volley from the middle of the court keeps the Swiss in there, and he has deuce after a casual drop-shot from Murray goes long. Big moments coming up, but the Wimbledon champ comes through. Wawrinka's play has been that good that he has yet to give Murray a sniff of a break point.

It's relentless from the world number 10, who drills himself to a 30-0 advantage. An ace brings up 40-0, bringing a deflated look from Murray, and he is made to feel worse after an exquisite drop volley at the net.

Wawrinka finds the line with a winner for 15-15, but he shanks a second-serve return to give Murray a little bit of breathing space. The Scot needs it, after another volley at the net has Murray on the run to no avail. I'm running out of superlatives to describe Wawrinka's shots in this match - he cracks a backhand from behind the baseline for deuce. Murray then nets an easy put-away, and it is break point to Wawrinka. Dear oh dear...a double fault from Murray and that could be that.

Stan the man eases to 30-0, but for once, he misses with a forehand. Murray can't latch onto a second serve though, and it's two game points for Wawrinka. We are just short of the two-hour mark and Murray is on the verge of losing his grip on the US Open trophy.

There's just too many errors coming off Murray's racquet, and even when he does play a good point, Wawrinka is drilling winners from all parts of the course. He has 15-30, but he can't capitalise on a poor second serve. Murray somehow holds, but it isn't looking promising. Remember, he has yet to bring up a break point.

Wawrinka opens with a double fault, and Murray is quickly lifted, but his opponent hits back with a dominating point. MAGICAL from Wawrinka, who serves out wide before executing a fine drop shot. But Murray has 30-30 when Wawrinka drifts a shot long of the baseline. It's all set up for Murray to create the break point he has been searching for, but he makes the error, and Wawrinka holds his nerve to move two away from the last four.

BREAK! A fine return from Wawrinka forces Murray to go wide with a volley, before Murray sends the ball a few metres long of the baseline. 0-30 down and Wawrinka is nearing the finish line. Murray pulls a point back, but that is stunning from the 28-year-old, who wrong-foots his opponent with a backhand volley. Two virtual match points, but Murray saves the first with a stupendous backhand drop volley. He can't save the second, however, as Wawrinka drives a forehand out of the reach of Murray as he advanced to the net. Wawrinka will serve for the match and his first ever Grand Slam semi-final.

MATCH! Murray has changed the colour of his shirt. Mind games, perhaps? Wawrinka double faults, before Murray thumps a return winner. Wow, just wow. Murray chases down two balls before Wawrinka smashes a winner from the baseline. Another forehand winner brings the game to 30-30, and it is MATCH POINT to Wawrinka, who converts another smash. Can he do it? The answer is yes, as Murray nets a return. Andy Murray is out of the US Open.

There's not much you can say to that, apart from just sit here and be in awe of the performance that Wawrinka just produced. Murray was nowhere near his best, but he has been completely dismantled by the best display of Wawrinka's career.

The startling stat is that Murray didn't create a single break point. Not one. How many times have we said that during his career?

Wawrinka will now move on to the semi-finals, where he will play either Novak Djokovic or Mikhail Youzhny. Murray, on the other hand, will return in Croatia for Great Britain's Davis Cup tie. Well, that's the intention anyway.

That will be all from Sports Mole this evening. Thank you for joining us. Goodbye for now.