Andy Murray
Andy Murray on his way to victory against John IsnerGetty Images

Andy Murray eased past John Isner in straight sets (7-6 (11-9) 6-4 6-3) to reach the quarter-finals of the French Open. The 29-year-old Brit produced another impressive performance, following his encouraging win against Ivo Karlovic, to defeat his big-serving American opponent at Roland Garros.

The match-turning moment arrived at the end of the first set, which went to a 16-minute tie break. Murray saved a set point on Isner's serve by sending a nerveless backhand down the line and past his onrushing opponent. He saved two more before taking the all-important first set.

The world number two did not lose his serve at all during the rain-interrupted match and sealed victory against the 15th seed with an ace. Now, Murray will face either Japanese fifth seed Kei Nishikori or home favourite Richard Gasquet of France in the last eight.

"It was very important to win that first-set tie-breaker. It was a very close opening set and it could have gone either way," Murray explained after the match, according to the BBC. "I got lucky with the opening set point that Isner had in the first, I guessed the right way and got the winner.

"It was difficult conditions with the rain and to go into the rain delay with an advantage was very important."

Murray's form has gradually improved through the course of the tournament, and the Brit will now be confident of making the semi-finals at Roland Garros for the fourth time in his career.