Welcome to our LIVE coverage of Andy Murray's US Open quarter-final clash with John Isner. Murray is the clear favourite but the big-serving American has home advantage as a likely clash with Rafael Nadal is on the cards.

MURRAY 7-5 6-4 3-6 7-6 (7-2) - Surely that is that. Isner has the whole court to volley into and he inexplicably volleys into the net. Two good serves and Murray wins…job half done as Isner fails to pull off the drop shot…and completely done! Isner batters the return well wide. Murray through to the semis.

MURRAY 7-5 6-4 3-6 6-6 (4-2) - Murray with first serve and he takes the first point. Isner responds with a big serve, but double faults in the following point to hand Murray the mini-break. Murray extends his advantage with the 1-2 out wide. A scintillating backhand crosscourt winner completes the minibreak…at the turnaround it's a single break. This is tense.

MURRAY 7-5 6-4 3-6 6-6 - A big second serve into the body and a boomer of a forehand out wide is a brave way for Isner to move ahead. He takes the game when Murray slices his next return into the net. Tie Break Time

MURRAY 7-5 6-4 3-6 6-5 - Isner with a terrible forehand on the first point of this crucial game…Murray is not happy as a line judge incorrectly calls his shot out and the judge has to overall as Isner is struggling. Murray's footwork is all wrong and he will rue that missed point. Murray hits a passing shot he'd usually bury well wide. Nerves from the American as he hits an incredibly easy volley wide…Murray's two points from the match…

MURRAY 7-5 6-4 3-6 6-5 - A great second serve from Murray into the body for the point. Isner should really pass the Scot, but hits his attempt into the net. 40-15 and Murray hits a clean backhand winner down the line.

MURRAY 7-5 6-4 3-6 5-5 - Isner fails to clear the net with a half-volley and it's 15-15. Murray badly slips, but Isner only just gets the volley in with the Scot on the floor. Murray replies with a stinging winner up the line. He can't draw to deuce though as he miss times a forehand return.

MURRAY 7-5 6-4 3-6 5-4 - ...Isner nets in the next point and Murray can get himself out of trouble…but the American hits a big forehand down the line. Murray worryingly feels his back after serving, but he's fine after playing out a devastating rally which he wins when Isner comes to the net and gets passed with a brutal forehand.

MURRAY 7-5 6-4 3-6 4-4 - An 89mph ace from Murray. He goes for that trusty drop shot, but it this time clips the top of the net. Incredible point there! Murray again plays the drop shot, but Isner gets there. They take it in turns to dink it over before Isner tries a lob. It's not brilliant, but Murray volleys wide. The American has two break points…an ace down the tee reduces the arrears. Murray saves the break - a serve only just lands in and he pulls off a brilliant volley for deuce...

MURRAY 7-5 6-4 3-6 4-4 - Isner replies, coming in behind his serve and playing a gentle volley low over the net that barely bounces, taking the game to 15.

MURRAY 7-5 6-4 3-6 4-3 - Each player is cruising on serve and Murray continues the trend, winning to 15.

MURRAY 7-5 6-4 3-6 3-3 - Murray looks incredibly frustrated as there is nothing he can do when the big American is serving this world. Isner is apparently carrying an inury to his ankle, but it doesn't look like it at the moment. One of many smashes hits the back wall and that's the game.

MURRAY 7-5 6-4 3-6 3-2 - Another perfectly executed drop shot from Murray. His eleventh ace gives him the lead in this fourth set.

MURRAY 7-5 6-4 3-6 2-2 - Murray starts to apply the pressure again. He goes 0-30 up as Isner fails to keep a volley within the lines. Isner responds with a 137mph serve. A 136mph ace out wide draws him level and a 115mph second serve into the body puts him up in the game. A serving masterclass. Murray lobs wide on the final point.

MURRAY 7-5 6-4 3-6 2-1 - A brutal backhand down the line from Isner that leaves Murray off balance. Isner is just battering it off both wings now. A forehand winner up the line gives him a glimpse of the break. Murray responds with some solid hitting. An ace sliced out wide and an unreturnable serve keeps the Scot moving in this set.

MURRAY 7-5 6-4 3-6 1-1 - What. A. Rally. Both players hustle at the net, dinking and slicing back and forth, but it is Isner that comes out on top. Isner lays the smackdown with a serve out wide and the fourth set is level.

MURRAY 7-5 6-4 3-6 1-0 - A 79mph second serve isn't quick enough from Murray and Isner punishes it with a fierce forehand winner. The wrong choice of shot from the American as he tries the drop shot from a tough angle. Murray hits a backhand winner down the line and wraps the game up when Isner fires into the net.

MURRAY 7-5 6-4 3-6 - SET! Isner is racing through his service game and he works to 40-0. Three set points, Murray saves one but the American's 13th ace of the game takes it.

MURRAY 7-5 6-4 3-5 - The game's hit a bit of a lull and the crowd are a bit subdued. Murray takes the game to 15 with consummate ease.

MURRAY 7-5 6-4 2-5 - There's no stopping Isner though as his ever improving first serve percentage is making each service game easier. He takes this game to love, the last point courtesy of a booming serve out wide.

MURRAY 7-5 6-4 2-4 - Bad idea to come to the net when you put the approach into Murray's hitting zone. The Scot digs in and gets to 40-40 and eventually takes the game.