German Tommy Haas edged out his practise partner Marat Safin [Images] 4-6, 6-3, 2-6, 6-2, 7-6 on Wednesday to reach the quarter-finals of the U.S. Open for the second time in three years.

Former champion Safin led 3-1 in the deciding tiebreak but 14th seed Haas came back to win it 7-5 and set up a clash with another Russian Nikolay Davydenko.

"I'm really excited that I am back in the quarter-finals once again," Haas said.

"Basically it was just the last two points -- it is a flip of a coin when you get a fifth-set tiebreak."

Twice Safin led by a set but Haas, who beat Robby Ginepri on a fifth-set tiebreak in round three, took advantage of a loose set from the Russian to force the decider.

Neither man could earn a break point in the fifth set but Safin missed a simple volley at 3-1 in the tiebreak and Haas held his nerve to clinch victory on his first match point.

Andy Murray bows out

Andy Murray's hopes of a first Grand Slam quarter-final ended in disappointment when he was beaten 6-1, 5-7, 6-3, 6-0 by seventh seed Nikolay Davydenko of Russia [Images].

Resuming at two sets to one after the fourth-round match was held over from Tuesday because of rain, Murray made 13 unforced errors in the fourth set and Davydenko cruised to victory.

The 19-year-old Scot was broken in the first game of the fourth set and from then on he was always playing catch-up.

Davydenko, who had never before been beyond the third round at the U.S. Open, broke again in the third and fifth games and served out for a clash with 14th seed Tommy Haas.

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