US Open - Murray outclasses Tsonga to set up Djokovic showdown

Murray had not beaten a top-10 player since his emotional victory over Djokovic on Centre Court more than a year ago but played a very fine match in the New York heat to defeat ninth seed Jo-Wilfried Tsonga 7-5 7-5 6-4.

It maintained the Scot's impressive record of having reached at least the quarter-finals of every grand slam tournament he has played in for the past four years.

Murray said: "It was extremely tough conditions, very humid. It started to cool down a bit at the end but the first two sets were very long, tough sets and mentally quite draining. I'm glad I managed to get through."

The 27-year-old will meet his long-time rival Djokovic at a slam for the first time since Wimbledon in the last eight on Wednesday and for the first time at Flushing Meadows since his maiden grand slam triumph two years ago.

"It will be a tough match," said Murray. "We've had a lot of long ones, there are normally a lot of rallies. We had a long one here a few years ago; I've obviously got great memories from that match.

"Hopefully we can play another top-level match. If I play well, I have a chance."

Murray had beaten Tsonga in nine of their previous 11 matches but lost the most recent one in Toronto last month from 3-0 up in the final set.

It was the first time Tsonga had beaten his former junior rival in a competitive match for six-and-a-half years.

The Frenchman revealed ahead of the clash that there was no longer the same fear factor about Murray in the locker room, and he also sensed there was not the same power in Murray's serve and groundstrokes.

There was nothing wrong with the eighth seed's serve in the first set, though, Tsonga managing just three points on it.

The disappointment for Murray was that he could not capitalise on Tsonga's early edginess but more chances arrived in the 12th game and he took his second set point thanks to a fine backhand return.

Murray certainly looked more comfortable back on Arthur Ashe Stadium and away from Louis Armstrong, where he dropped sets against both Robin Haase and Andrey Kuznetsov.

Things began to get sticky early in the second set, though, Murray finding himself under pressure on serve for the first time in the third game and responding with a drop shot that limped into the net.

He had two chances to level at 3-3 but was a little passive both times and was beginning to cut a frustrated figure.

He did not have to wait long for more chances, with two in the eighth game. Tsonga saved the first with an ace but on the second Murray powered a forehand winner into the corner.

Suddenly the 2012 champion looked the more likely winner of the set, and again he struck in the 12th game, seizing on a second serve.

Tsonga had been having a poor season until Toronto when he beat 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, but the odds were massively against him now.

The conditions were arguably tougher than when Murray cramped so dramatically against Haase last Monday but 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.

There was a far bit of ranting and raving - and some choice language - but Murray kept his focus well and played the shot of the match in the sixth game, slamming a running forehand cross-court winner off a decent Tsonga smash.

The pressure was all on the Frenchman serving to stay in the match at 4-5 and successive double faults was a dreadful way to start.

Murray nailed a backhand winner to bring up three match points and took the second when a tired-looking Tsonga placed a backhand long after two hours and 35 minutes.