Djokovic, Sharapova headline day one at US Open

Novak Djokovic during his Wimbledon match against Roger Federer in southwest London on July 6, 2014 - by Carl Court

The world number one from Serbia and women's French Open champion Maria Sharapova are the star attractions on the opening day of the year's last Grand Slam -- set to shine under the lights on Arthur Ashe Stadium court.

With two-time defending women's champion Serena Williams and five-time men's champion Roger Federer waiting in the wings, Monday's slate featured two other former champions in Andy Murray and Venus Williams, along with 2014 Australian Open winner Stan Wawrinka and women's world number two Simona Halep.

World number one Djokovic, recently married and soon to be a father for the first time, is gunning for a fifth straight US Open finals appearance and a second title to add to the one he won in 2011.

He was set for a first career meeting with Diego Schwartzman, a 22-year-old from Argentina who is playing in his second career Grand Slam and the first tour-level hardcourt tournament of his career.

"I know he's very quick on the court," Djokovic said. "He's had his best results on clay. It's obviously always tricky to play against somebody I never faced before. And playing on the center court for Schwartzman will be a unique experience. 

"He definitely has nothing to lose. I'm going to try to use my experience playing many matches on the center court and get a win."

Sharapova, who won her fifth career Grand Slam title at Roland Garros this year, returns to Flushing Meadows after missing last year's US Open with a shoulder injury.

Although the former world number one is now sixth in the world rankings and seeded fifth, she's a favorite to challenge defending champion Williams for the title.

Sharapova acknowledged that first round opponent Maria Kirilenko was a potentially tough foe.

A former top-10 player, Kirilenko has dropped to 113th amid a spate of injuries and hasn't played since Wimbledon.

Sharapova has won five of their seven career meetings, but fellow Russian Kirilenko has gotten the better of Sharapova on a major stage -- at the Australian Open in 2010.

One of their most memorable clashes came at Indian Wells in 2012, where Kirilenko was penalized for noisily tapping her racquet like a hockey stick as Sharapova set up for a shot.

"It's one thing if you do it once, but I think she did it three or four times," Sharapova said at the time. "She forgot, I think, the sport."

- First match always tricky -

Earlier on Ashe, two-time US Open winner Venus Williams, 34, took on 43-year-old Kimiko Date-Krumm of Japan, and Switzerland's Wawrinka, the third seed, faced Czech Jiri Vesely.

Eighth-seeded Murray, who hasn't reached a final since winning Wimbledon in 2013, faced a potentially awkward opener against Robin Haase of the Netherlands.

Halep, runner-up to Sharapova at Roland Garros, shook off first-round jitters to defeat unranked US wildcard Danielle Rose Collins 6-7 (2/7), 6-1, 6-2.

Halep survived 33 unforced errors to put away US collegiate standout Collins in just under two hours.

In contrast, Polish fourth seed Agnieszka Radwanska needed just 47 minutes to rout Canadian Sharon Fichman 6-1, 6-0.

Radwanska, who has never got beyond the fourth round in New York, allowed her 112th-ranked opponent just three points in the second set.

"First match is always tricky, but I think today everything was working my way -- a pretty good start for me," said Radwanska, who warmed up for the US Open with a title in Montreal.

The world number five said she has her sights set on reaching the quarter-finals -- as she has at least once at every other Grand Slam.

"I will do everything to do that," she said. "I hope (to go) even deeper, but let's focus on that first and then we will see."