By Steve Keating
NEW YORK (Reuters) - It was the Labor Day holiday in the United States on Monday but Andy Murray came to Arthur Ashe Stadium ready to work, demolishing Grigor Dimitrov 6-1 6-2 6-2 to storm into the quarter-finals of the U.S. Open.
With the year's final grand slam entering its second week Murray dispatched the 22nd seed in just two hours, signaling he is well prepared to extend a dream summer that has included a second Wimbledon title and a second Olympic gold medal.
Bulgarian Dimitrov had ended Murray's title defense at Wimbledon in 2014 and came out on top in their last meeting earlier this season in Miami but the second-seeded Scot was firing on all cylinders on Monday.
He rated the match, which included a career-fastest 141-mph ace to close out the first set, as one of his best this season.
"It was definitely up there," said Murray. "I played very well today with very few unforced errors and made it very tough for Grigor.
"That would be the fastest serve I've hit, the other best serve was here at the U.S. Open around 138 but I have never hit over 140.
"I think that was lucky, I only did it once."
Dimitrov held his first serve but Murray then tore through the next five, wrapping up the set in 30 minutes and capping it off with a blistering ace.
The Scotsman broke Dimitrov twice to open the second and take a 3-0 lead, then broke the Bulgarian again to open the third, never giving him a chance to get back into the match.
"I don't think he started the match really badly," said Murray. "He had a couple of breakpoints in the first game but once I got up in the score, wasn't giving him any free points, I could sense it was getting tough for him.
"I just wanted to keep my foot on the gas.
"I didn't give him an opportunity once I was ahead to let him back in the match."
Next up for Murray is Japan's Olympic bronze medalist Kei Nishikori, a 6-3 6-4 7-6(4) winner over Ivo Karlovic.
"I have played well against him in the past but he likes these conditions," said Murray. "He plays well in New York. He's made his only slam final here. He beat Novak (Djokovic) here.
"He's obviously, I think, playing pretty well this summer."
(Editing by Larry Fine/Peter Rutherford)