Andy Murray through to US Open quarter-finals

Andy Murray has progressed to the US Open quarter-finals with a four-set victory over Denis Istomin.

The defending champion struggled in the first set but forced his way back in the following three, eventually winning the fourth-round contest 6-7(5) 6-1 6-4 6-4.

The Briton was initially frustrated with a number of bad line calls and windy conditions, but then found his footing and wrapped up the match in just over three hours.

The 26-year-old went down in the first set from a winning position of 5-3, but broke at the start of the second with a cross-court forehand winner. He made just two errors off the ground thereafter and emerged victorious in nine of the 11 games to once again dominate in the third.

For a brief moment Istomin appeared to make it a contest in the third set when he crawled back to 3-3, but Murray held his own, closing it out 6-4 and then dominating the fourth.

Murray will face Stanislas Wawrinka for a place in the semi-finals.