NEW YORK (AP) -- Serena Williams was so dominant in the first round of the U.S. Open, her opponent really wanted a hug.
So midway through the second set of defending champion Williams' 6-0, 6-1 victory Monday night, Francesca Schiavone wandered behind the baseline, found a ball boy and enveloped him in a full-fledged embrace.
"I don't need a hug in that moment,'' Schiavone joked afterward. "I need a game.''
It was that kind of evening for Schiavone, an often-demonstrative player who is certainly no pushover: She won the 2010 French Open, was the runner-up at that Grand Slam tournament a year later, and twice has been a quarterfinalist at the U.S. Open. She's been ranked as high as No. 4 but is 54th this week.
"I knew playing a former Grand Slam champion in the first round was a really, really tough draw,'' Williams said, "so I tried to be super serious.''
All told, the match only took an hour. And it ended right in time, as far as Williams was concerned, because a light rain began to fall just at the conclusion in Arthur Ashe Stadium. Eventually, play was suspended for the day, and the last scheduled match of the night session, 17-time major champion Roger Federer vs. 62nd-ranked Grega Zemlja of Slovenia, was postponed until Tuesday.
The No. 1-ranked and No. 1-seeded Williams was nearly perfect, never facing a break point, making only eight unforced errors, compiling a 13-3 edge in winners, hitting serves faster than 115 mph, and taking the first 10 games. Schiavone didn't help herself by hitting eight double-faults.
"It was tough today,'' said Schiavone, who is working with Peter Lundgren, one of Federer's former coaches. "Really, really tough.''
When Schiavone finally got on the board more than 50 minutes into the match, holding serve to win her first game with a volley winner, she swung her right fist in a celebratory roundhouse punch and shouted. Her face then broke into a wide smile while she strutted to the sideline, and she tossed her racket toward her changeover chair.
"It was very, very nice to win a game,'' Schiavone said. "For the first time in my life, I felt joy from winning a single game.''
Earlier, with the outcome already in no doubt at 6-0, 2-0, Schiavone found herself facing yet another break point. She made her way to a ball boy, rested her head on his right shoulder, and squeezed him tight. Moments later, with Williams having wrapped up the break, Schiavone went to sit down in her seat, put her palms in the air and shrugged, as if to say, "What can I possibly do against her tonight?''
At Williams' news conference, she was asked by an Italian reporter: "Did you really want to win 6-love, 6-love against the poor Schiavone?''
That drew a chuckle from Williams, who responded: "No, it wasn't that. I was just out there, trying to be focused.''
She is seeking her fifth U.S. Open championship, and 17th Grand Slam title overall. She improved to 61-4 in 2013 and has won eight tournaments.
Earlier in the day, on the same court, and after two years of illness and injury, Serena's sister, Venus, pulled off an upset win when she defeated Wimbledon semifinalist Kirsten Flipkens. Venus Williams had been 14-0 in the first round of the U.S. Open, though she never had to face an opponent ranked in the top 30 at that stage.
Her ranking down to No. 60, Williams beat the 12th-seeded Flipkens 6-1, 6-2 for one of her biggest wins since she pulled out of this tournament two years ago because of Sjogren's syndrome, an autoimmune disease.
"For me, I stay positive because I know I can play great tennis,'' Williams said. "Sometimes you just have to go through more than what you want to go through. Sometimes you have to have losses. When I had losses, it always motivates me a lot to do better and to work harder.''
The 33-year-old looked strong Monday, purple braids poking out of her visor that matched her floral dress. Williams fought off three break points at 2-2 in the second set in a game that went to six deuces.
"I haven't had a lot of time to talk to her, but I was really happy she did well,'' Serena said about Venus. "She's really inspiring to me.''
Bothered by a lower back injury, Williams was playing just her third event since a first-round loss at the French Open. She hadn't defeated a top-20 opponent since last October.
"I realize that I haven't had a lot of chances to play this year or a lot of chances to play healthy this year, have had injuries and what have you,'' she said. "So I'm just going to have to keep working my way into it maybe more than some of the other players. But I know I can do that.''
Flipkens, meanwhile, had been enjoying a career year. The Belgian had never reached the round of 16 at a major tournament before the Australian Open, then made her run at Wimbledon.
American Sloane Stephens overcame numerous deficits Monday to pull out a 4-6, 6-3, 7-6 (5) victory over Mandy Minella of Luxembourg in the first round of the U.S. Open.
Stephens, seeded 15th, lost the first set to the 110th-ranked Minella and trailed 4-2 in the third, then 3-1 in the final-set tiebreaker.
Stephens won five straight points from there, then closed it out on her third match point to improve to 9-1 in the first rounds of majors.
This was the second time in three years Stephens needed a third-set tiebreaker to win her opening match at Flushing Meadows.
Stephens made her first career Grand Slam semifinal earlier this year at the Australian Open, then followed that by making the fourth round at the French Open and quarterfinals at Wimbledon
Rafael Nadal looked quite comfortable in his return to the U.S. Open, beating American Ryan Harrison in straight sets.
The second-seeded Spaniard won 6-4, 6-2, 6-2 in the first round Monday. Nadal, the 2010 champion, skipped last year's U.S. Open because of a left knee injury. He was playing his first Grand Slam match since an opening-round loss at Wimbledon.
Nadal improved to 16-0 on hard courts this year. The 21-year-old Harrison is 0-20 against top-10 opponents.
Both players had 28 winners, but the 97th-ranked Harrison had made 34 unforced errors to 21 for Nadal. The 12-time major champion pounced on Harrison's second serve, winning 71 percent of the points on it. And with Harrison getting in just 62 percent of his first serves, Nadal had plenty of chances to break.
In the day's first big upset, a British man not named Andy Murray - 179th-ranked qualifier Daniel Evans - stunned 11th-seeded Kei Nishikori in straight sets. Evans won 6-4, 6-4, 6-2 in his U.S. Open debut.
Both are 23, but Nishikori was playing in his 17th Grand Slam event, with a 25-16 record coming in. Evans was 0-2, both matches at Wimbledon.
"I was pretty calm today,'' Evans said. "It wasn't that much of a big deal what was happening on the court. I wasn't nervous serving it out.''
Third-seeded Agnieszka Radwanska and fifth-seeded Li Na advanced in straight sets on the women's side. Radwanska beat Silvia Soler-Espinosa 6-1, 6-2, while Li defeated Olga Govortsova 6-2, 6-2.
Radwanska withdrew from her last tournament at Cincinnati on Aug. 15 before her quarterfinal against Li to fly home for her grandfather's funeral.
No. 16-seeded Sabine Lisicki, the Wimbledon runner-up, beat Vera Dushevina 6-2, 7-6 (3), while 23rd-seeded American Jamie Hampton defeated Lara Arruabarrena 6-4, 6-2.
American teen Lauren Davis lost by a "double bagel,'' falling to 18th-seeded Carla Suarez Navarro of Spain 6-0, 6-0 in 57 minutes.
On the men's side, eighth-seeded Richard Gasquet eliminated American Michael Russell 6-3, 6-4, 6-2. Bernard Tomic rallied past Albert Ramos in five sets, winning 6-3, 3-6, 4-6, 7-6 (1), 6-3 in nearly four hours.
The day started with some big news from a veteran U.S. player: Three-time Grand Slam quarterfinalist James Blake announced he would retire after the tournament at age 33.
Roger Federer is 32, and his struggles this year have him hearing questions about how much longer he'll play. The five-time U.S. Open champ is seeded seventh, his worst since 2002.
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