US Open 2011: Andy Murray beats John Isner to make semi-finals

Murray has made all four Grand Slam semi-finals in 2011

Andy Murray gave a resilient display to beat big-serving American John Isner and reach the US Open semi-finals.

The British number one came through a gruelling match 7-5 6-4 3-6 7-6 (7-2) in three hours and 24 minutes to remain in contention for a first major title.

A single break of serve in the opening two sets put Murray in control but Isner rallied in the third and pushed his opponent all the way in the fourth.

Murray will face reigning champion Rafael Nadal in the semis on Saturday.

The Spaniard thrashed 2003 champion Andy Roddick 6-2 6-1 6-3 in the last of the quarter-finals.

"I'm really happy to get through," said Murray. "He started serving very well as the match went on and it came down to a few points.

"I played really well, especially in the fourth-set tie-break. I went for my shots, served well and returned well.

"Three-and-a-half hours in that heat isn't easy. Hopefully they [Nadal and Roddick] will have a long one too so both players are in same boat tomorrow.

"I know I can win against either of them. I beat Rafa here before [in the 2008 semi-finals]. Andy will have huge support. Both will be pretty challenging."

Murray has now reached the last four at each of the Grand Slam events in a single season for the first time in his career.

He outclassed Isner in their only previous meeting - at January's Australian Open - but the American gave a far better account of himself this time around.

Isner opened proceedings with a confident service hold before earning an immediate break point, only to ruin his chance with consecutive mistakes.

Neither player faced any serious trouble in the next eight games, but at 5-5 Murray upped the tempo to secure a vital breakthrough.

After two sensational crosscourt forehands took the Scot to 15-30, Isner produced an untimely double-fault and then went long with a forehand.

Murray served out the opener and made a brilliant start to the second set, targeting the Isner forehand and breaking to love with the 28th seed drilling into the net.

Murray was now on a roll and he moved 2-0 ahead with a booming ace before registering a further three break points in game three.

Isner responded well, a trio of aces averting the danger, but his unforced-error count began to rise sharply and Murray comfortably served out to extend his advantage.

Any hopes of a straight-sets victory were dented, though, as Isner struck in game two of the third and then saw off a break point to hold for 4-1.

Isner appeared to damage a foot in that game but showed little sign of discomfort in serving out the set with a massive ace.

There was nothing to choose between the pair in the fourth until Murray fell to 15-40 in game nine - but, crucially, he saved both break points.

It went to a tie-break and Murray came into his own, dominating a nervous-looking Isner with some aggressive hitting to book his place in the semi-finals.