World number 65 Denis Istomin believes that beating Andy Murray at the US Open would be the biggest win of his career.

The two clash in the fourth round at Flushing Meadows on Tuesday, with the pair having met just once before.

However, the 26-year-old from Uzbekistan is relishing the opportunity to square off against the reigning champion.

"I'm looking forward to it," Istomin told reporters. "I've just played him once, I lost in two sets. But it was a close match. I will try to play the same tactics as I did there and we will see what happens.

"He's a great returner. He returns almost everything. The key is my serve. I will try to serve better than usual. He moves on the court incredibly but I will try to move him more and try to beat him.

"If I win, it will be the biggest match of my life. I'm looking forward to this match. I will try to play my game and concentrate on winning."

Murray advanced to the fourth round after beating Florian Mayer on Sunday.