US Open 2014: Andy Murray made to work for fourth round victory over Andrey Kuznetsov

Scot beats Russian 6-1, 7-5, 4-6, 6-2 to set up clash with Jo-Wilfried Tsonga

Andy Murrary celebrates winning against Andrey Kuznetsov (Getty)

Andy Murray is through to the second week of his 15th Grand Slam tournament in succession but there were times when he again had his supporters on the edge of their seats here. Although the 27-year-old Scot beat Andrey Kuznetsov 6-1, 7-5, 4-6, 6-2 to maintain his admirable record of consistency at the highest level, he will need to avoid some of the lapses he made against the world No 96 if he is to make further progress.

Murray, who has now reached the fourth round or better in 24 of his last 25 Grand Slam tournaments, started and finished well but dropped his serve four times with some careless play. In the fourth round he will meet Jo-Wilfried Tsonga, who beat Pablo Carreno Busta 6-4 6-4 6-4.

The match was played in Louis Armstrong Stadium, where Murray suffered so badly with cramp in his opening match against Robin Haase. This time, however, in considerably cooler conditions, the Scot looked in good physical shape. Kuznetsov knocked out Fernando Verdasco in the previous round and beat David Ferrer at Wimbledon, but the 23-year-old Russian was soon being given the run-around.

Murray took the first set in just 30 minutes with breaks in the second and sixth games. When he broke in the opening game of the second set with a splendid forehand cross-court pass he appeared in complete control, but at 4-3 Murray berated himself when a double fault enabled Kuznetsov to break back. At 5-5, nevertheless, Murray broke again before serving out for the set with an ace.

If the dropped service game hinted at a dip in concentration, worse was to follow in the third set. Kuznetsov broke to lead 3-1, Murray broke back to love in the seventh game thanks to some admirably bold returns, but played a poor game when he served to stay in the set at 4-5. From 15-15 Murray hit a wild forehand long, missed the target with an even more careless drive volley and then double-faulted.

Kuznetsov, however, was unable to take advantage of the swing in momentum as Murray quickly rediscovered his focus. The Scot broke to lead 2-1 in the fourth set and again two games later as Kuznetsov double-faulted on the last two points. There was still time for another slip-up from Murray, who netted two forehands in a row to enable Kuznetsov to retrieve one of the breaks, but the Scot broke back immediately and went on to serve out for victory after two hours and 35 minutes.

“I expected him to play well,” Murray said afterwards. “He obviously would have been confident from his last match. The first couple of sets were pretty good. Then I started a bit slow at the beginning of the third set. He gained confidence from that and he definitely started hitting the ball better in the third set.”

Murray said he hoped that the cramping issues which troubled him against Haase were now in the past. “Today was much better than Monday,” he said. “It was obviously cooler today, though it may have been a little bit more humid. It felt pretty humid on the court. It was quite cool actually by the end of the match.

“Yes, I hope it's not a problem for the rest of the tournament. As I said before the tournament started, I feel like I'm in very good shape. I trained extremely hard in Miami to get ready for this period of the year.”

Novak Djokovic, who is seeded to meet Murray in the quarter-finals, maintained his record of not dropping a set at the tournament when he beat Sam Querrey 6-3 6-2 6-2, while Milos Raonic ended 34-year-old Victor Estrella Burgos' remarkable run. The world No 80, who lost 7-6 7-6 7-6, became the first player from the Dominican Republic to break into the world's top 100 earlier this year and last week became the first from his country to win a Grand Slam singles match.

Raonic will now play Japan's Kei Nishikori, who beat Leonardo Mayer 6-4 6-2 6-3. Meanwhile Stan Wawrinka was handed a free passage into the fourth round when his scheduled opponent, Blaz Kavcic, withdrew from the tournament with a foot injury.

Petra Kvitova could have replaced Serena Williams as the world No 1 by winning the title here but the Wimbledon champion was swept out in the third round by a qualifier ranked No 145 in the world. Aleksandra Krunic, a 21-year-old Serb playing in only her second Grand Slam tournament, won 6-4 6-4 as Kvitova became the fifth of the top eight seeds to go out, joining Simona Halep, Agnieszka Radwanska, Angelique Kerber and Ana Ivanovic on the list of casualties. Krunic now faces Victoria Azarenka, who beat Elena Vesnina 6-1 6-1.

Williams booked her place in the last 16 with a 6-3 6-3 victory over Varvara Lepchenko, who was her third successive American opponent. Williams, who now faces Estonia's Kaia Kanepi, had lost a total of five games in her first two matches but was pushed harder by Lepchenko. “My opponent today was spectacular,” Williams said. “It was really a good match and it just shows how far Varvara has come.”