ANDY MURRAY recorded his best win since lifting the Wimbledon trophy last year to set up a blockbuster US Open quarter-final against Novak Djokovic.

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 quarterfinals 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.

Serena Williams reached her first grand slam quarterfinal of the year with victory over Kaia Kanep.

So far there have been none of the wobbles that led to unexpected defeats for the world number one in Melbourne, Paris and at Wimbledon.

She has not lost more than three games in any set and was a relatively comfortable 6-3 6-3 winner over her Estonian opponent on Monday.

Williams has looked totally focused on the job in hand this tournament and did not lose a point in her first three service games of the match.

Kanepi, another big hitter, kept pace with her initially but once Williams made the breakthrough for 5-3, the first set was gone.

Having broken again in the opening game of the second, there was an embarrassing moment for the two-time defending champion when she completely fluffed a smash and dropped her serve to love.

But it was soon forgotten, as was the eighth game when she served for the match and was broken, with Williams clinching victory on Kanepi’s serve.