US Open 2013: Andy Murray struggles through to quarter-finals in sluggish victory over Denis Istomin

Andy Murray loves the US Open, where he won his maiden Grand Slam title last year, but the world No 3 was back doing his Mr Grumpy impersonations for much of his fourth-round victory here over Denis Istomin.

Although he beat the 26-year-old from Uzbekistan 6-7, 6-1, 6-4, 6-4, Murray did not look happy for much of the evening. He complained about line calls and noisy spectators, had tetchy exchanges with the umpire and above all appeared frustrated at not making quicker work of his victory.

Perhaps Murray was aware that Novak Djokovic, the world No 1 and his potential semi-final opponent, had needed just 79 minutes to brush aside Marcel Granollers for the loss of just three games. Murray laboured for three hours and seven minutes to dispose of Istomin, who proved to be a stubborn opponent. The world No 65, whose bold flat ground strokes shot through the court, played a solid match and pushed Murray hard throughout.

Murray, nevertheless, is through to the quarter-finals here for the third year in succession and the fourth time overall. He has reached the quarter-finals or better of the last 11 Grand Slam tournaments he has played and is aiming to reach his fifth Grand Slam final in succession.

In the quarter-finals Murray will meet Stanislas Wawrinka, the world No 10, who sprang a surprise by beating Tomas Berdych 3-6, 6-1, 7-6, 6-2. Murray has won eight of his 13 meetings with Wawrinka and this will be their third meeting here. Murray won in straight sets in the fourth round in 2008, while Wawrinka won in the third round two years later.

The conditions were very different to Murray’s previous match, which was played in draining heat and humidity in the middle of the afternoon. This time the match in Arthur Ashe Stadium did not start until 8.35pm, by which time the temperature had dropped to a pleasant 23C and the humidity was much more bearable. There was a strong breeze, but it was less windy than it had been during the first match of the night session, and the temperature dropped as the evening wore on.

“It was definitely tough,” Murray said afterwards. “It was pretty breezy out there. It might not be that easy to see from the side, but on the court there was quite a strong breeze. Both of us were struggling a bit with our timing early on. But I thought we played some entertaining points. Sometimes when it’s windy like that you get some fun points.”

Istomin had won only one of his previous 20 matches against top 10 opponents, though he had enjoyed his first victory over a top-20 player at a Grand Slam event when he beat Nicolas Almagro, the world No 15, in the first round here last week. He had met Murray only once before, the Scot winning in the quarter-finals in Brisbane in January of this year.

Following the defeats of Lleyton Hewitt and Granollers, Istomin was the last unseeded player left in the competition and was attempting to become the first to reach the quarter-finals here for five years. He was also aiming to become the first Uzbek to make the quarter-finals of a Grand Slam tournament.

Murray had said after his third-round victory over Florian Mayer that he needed to start matches more quickly, but once again he was slow out of the blocks. For much of the first set the Scot looked comparatively sluggish and in the early games he appeared to have a problem with his left hip.

Four forehand errors by Murray gave Istomin the first break of the match, though the Uzbek made a mess of things when he attempted to serve for the set in the following game, a double fault enabling his opponent to break back.

Murray led 5-3 in the tie-break, upon which Istomin played his best point of the match so far, smacking a big forehand winner after cleverly manoeuvring himself into a position of strength. When Murray served at 5-4 he was distracted by a shout from the crowd and double-faulted, after which a forehand error and a wild backhand gave Istomin the set.

The Scot’s frustration at seeing nearly an hour’s work go to waste was evident when he walked back to his chair, but there could be no faulting his response. Murray came out for the second set looking much more positive, broke immediately with a big forehand winner and was soon 3-0 up. After a further break following a lengthy sixth game, Murray served out for the set in just 32 minutes.

Another early break put Murray in charge of the third set until a combination of some uncharacteristic errors and some solid hitting by his opponent saw Istomin level at 3-3. Murray appeared to be angry with himself for letting his advantage slip, but he kept his focus, broke back immediately and served out for the set.

The fourth set went with serve until Murray broke to lead 5-4, though he enjoyed a big slice of luck. A horribly shanked forehand by the Scot flew high into the sky but landed just inside the court and he went on to break after Istomin netted a forehand of his own. Murray served out for victory, letting out a big roar when he put away his match-winning overhead.

Asked what adjustments he had made after the first set, Murray said: “I just started trying to dictate the points a bit more, especially when I had the wind with me. I started trying to use my forehand a little bit more. That was basically it. I had a few chances to win the first set. I was up 5-3 in the breaker. I lost four points straight, so it was just minor adjustments.”

As for Wawrinka, Murray said he expected a very tough match. “He’s played great tennis the whole year,” Murray said. “He’s a very talented player. We played once before here on this court when we were much younger, but a lot has changed since then. So it’s going to be a very tough match.”