US Open 2014: Andy Murray through after beating Jo-Wilfried Tsonga in three sets

Andy Murray has beaten France's Jo-Wilfried Tsonga 7-5 7-5 6-4 in the fourth round of the US Open.

Tsonga had been having a poor season until Toronto when he beat Novak Djokovic, Murray, Grigor Dimitrov and Roger Federer back to back to lift the joint biggest title of his career.

That took him back into the top 10 and set him up perfectly for the year's final grand slam.

It was a long way back now, though, particularly given the heat and humidity the pair were playing in.

The conditions were arguably tougher than when Murray cramped so dramatically against Haase last Monday but so far there was no sign of any physical discomfort.

What was the same, however, was that Murray had a dip at the start of the third set, serving a double fault to go break point down before Tsonga powered away a return.

He had to work very hard to avoid trailing 3-0, saving two break points, and he got his reward in the next game, breaking back to love to make it 2-2.

Murray had talked in the build-up about the need to recover from any dips quickly and he was certainly doing a good job at that.