* Murray wins despite service struggles
* Federer, Clijsters, Azarenka record straight-sets wins
* Sharapova breezes by Czink in first match since Olympics (Updates with Federer quotes)
Andy Murray's serve was anything but golden on the opening day of the U.S. Open but the Olympic champion still had too much firepower for Alex Bogomolov Jr. and led a parade of favorites into the second round on Monday.
The top guns had little trouble making it through their first-round encounters, with world number one Roger Federer, three-times champion Kim Clijsters, and top-seeded Victoria Azarenka hardly breaking sweat.
Murray was at his best when it mattered most, recording a service break in a healthy nine of 19 chances against the 29-year-old Russian to win 6-2 6-4 6-1 in two hours, 15 minutes.
However, the Scotsman, who beat Roger Federer to win the gold medal at the London Games in what he called his best career victory, successfully landed only 49 percent of his first serves in humid, windy conditions against Bogomolov.
"I played fairly well from the back of the court. I just would have liked to have served a bit better because I wasn't getting many free points on my serve," said Murray, looking for his first grand slam title.
"Because of that, there were a lot more rallies. When he's in a rhythm, he's tough to break down."
Federer, seeking his sixth title at Flushing Meadows, dismantled American Donald Young 6-3 6-2 6-4 while Clijsters overwhelmed American teenager Victoria Duval 6-3 6-1.
Not to be outdone, Azarenka, seeking her second major title after winning this year's Australian Open, blew past Russian Alexandra Panova 6-0 6-1 in just 50 minutes.
Defending champion Samantha Stosur needed only 51 minutes to blitz Croatia's Petra Martic 6-1 6-1, while 2006 U.S. Open winner Maria Sharapova blew by Hungary's Melinda Czink 6-2 6-2.
Federer landed 70 percent of his first serves and had seven aces to defeat Young, a former junior champion who snapped a 16-match losing streak in an ATP event in Winston-Salem last week.
"It was good considering I played a very talented player who I didn't know much about and never played against," said Federer. "First round of the U.S. Open can always bring a lot of pressure with it.
"It was very windy out there and extremely humid. I'm just happy I was able to weather the conditions and a dangerous opponent. Overall I'm extremely happy."
Clijsters, who will retire after the tournament, said she was not scared that her match against Duval under the lights at Arthur Ashe Stadium could be her last.
"I didn't really think about that," said the 29-year-old Belgian. "I was just excited to be out there and to have the opportunity to play in this kind of condition, prime time.
"A night match, it's always a very special occasion. The energy, when you step out on court also after the opening show, the stadium was almost full.
"So it was a lot of fun to go out there. But still a bit nervous, too."
Stosur said it was "fantastic" to take the court in defense of her title.
"It was great to get out there again," said the Australian seventh seed. "I felt like I was ready to go. First match up, first day, was a good start, so I certainly won't complain about being out there."
Stosur lost in the first round of the Australian Open and the Olympics and was beaten in round two at Wimbledon but her rout of Martic suggested she will not relinquish her U.S. Open crown without a fight.
She won the first 19 points of the match before giving Martic a gift and ending the prospect of a 'golden set'.
"I hadn't missed a point and the match had been going pretty quick and obviously in my favor," said Stosur, who blasted 10 aces in the victory. "(The idea of a golden set) did pop into my head for a split second but then I hit the double fault and it was erased and I was quickly on with the next point."
Shortly after the 28-year-old Stosur left the court, fans scrambled for cover as heavy rain pelted the National Tennis Center grounds at Flushing Meadows.
The rain caused a two and a half hour delay and threatened to wreak havoc on the schedule but the sun reappeared to create steamy conditions and play resumed.
Third seed Sharapova enjoyed a 24-8 advantage in winners and lost her serve to Czink only once in swirling wind to set up a second-round match against Lourdes Dominguez Lino of Spain.
"I haven't been far here, past the first week, in a long time," said Sharapova, playing her first match since winning a silver medal at the Olympics. "I would love to get that back. I haven't played at a level that I wanted to play here.
"There shouldn't be any reason why I can't, having the success that I had for a few years, winning it in '06. That's certainly something that I'm looking to get back."