(Adds details, quotes)
* He topples Benneteau to advance
* Wawrinka next for fifth-seeded Czech
By Will Swanton
NEW YORK, Sept 1 (Reuters) - Czech dangerman Tomas Berdych marched towards a possible U.S. Open showdown with defending champion Andy Murray when he reached the fourth round with a commanding performance at Flushing Meadows on Sunday.
Serving powerfully and nailing 36 winners, the fifth seed swept past 31st-seeded Frenchman Julien Benneteau 6-0 6-3 6-2 in one hour and 54 minutes of near-flawless ball striking on the Grandstand court.
"It was a bit hot, a bit humid, but otherwise the tennis was good," Berdych said. "Finally I managed to stay focused from the first point until the last.
"I didn't do any ups and downs. I just took all the chances I had."
Berdych faces Swiss Stanislas Wawrinka in the fourth round ahead of a potential quarter-final clash against Britain's Murray. The ninth-seeded Wawrinka won a thriller on Louis Armstrong Stadium, beating Cypriot Marcos Baghdatis 6-3 6-2 6-7(1) 7-6(7).
Berdych reached the quarter-finals at the Australian Open and Wimbledon this year after guiding the Czech Republic to victory in the 2012 Davis Cup. He proved his big-match pedigree by topping 17-times major champion Roger Federer at Flushing Meadows last year before losing to Murray in four sets in the semi-finals.
"So far my career goes up and I'm climbing higher and higher, which is good," he said earlier this week.
"It's a matter of if I can stay patient. I feel good on the court. I have good rhythm, hitting the ball cleanly. That's what I need for my game.
"When you have more and more years, you have more and more experience. In tennis, all the things need to click together. Hopefully it's going to be a good Open."
Berdych is flying so far under the radar that his post-match news conference on Sunday amounted to one question.
Wawrinka has a 6-5 head-to-head record against Berdych. They have traded victories in their two meetings this year.
"It's always tough to play against him," Warinka said. "Usually we have some great battles together. I need to adapt a little bit my game because he's so powerful. He's not really happy to play against me. He doesn't like my game.
"We practice a few times together. I know if I'm if fit and if I play well, I have some chance."
(Editing by Gene Cherry)