Melbourne: After tumbling to the court and needing a medical timeout in the first set for treatment on her right ankle, Serena Williams got up and beat Edina Gallovits-Hall 6-0, 6-0 in her first-round match at the Australian Open.
The No. 3-ranked Williams is highly favored to win the Australian Open and came into the season's first major with 35 wins from her previous 36 matches, including titles at Wimbledon, the London Olympics and the US Open.
The injury could be a significant setback as she seeks a third consecutive Grand Slam title. It could be a boost for the likes of defending champion Victoria Azarenka, who was down a break in the second set but beat Monica Niculescu 6-1, 6-4 on Rod Laver Arena.
The world number three and five-time Australian Open champion beat her Romanian opponent 6-0, 6-0.
Andy Murray had won his first match as a Grand Slam champion in the earlier match on Rod Laver, beating Robin Haase of the Netherlands in straight sets.
With a packed program on the center court at Melbourne Park, Williams was playing on the second of the show courts.
The 31-year-old American left Hisense Arena without stopping for the customary courtside TV interview and was expected to have tests immediately on her ankle.
Williams was leading 4-0 after 19 minutes when she fell awkwardly chasing a ball wide on her forehand side, putting both hands over her face.
She rolled from her back up onto her hands and knees, where she stayed for several minutes before she was helped to her feet. The 15-time major winner started limping before easing into a walking stride as she made her way to the chairs on courtside to have her already heavily-taped ankle treated and then re-taped.
Williams won the first point after the medical timeout, approaching the net to hit a crosscourt winner without seeming to be troubled by the ankle. She hit two more forehand winners to win the game and go up 5-0, then called the trainer back to the court to adjust the taping on the ankle during the changeover. She had more treatment after winning the first set.
Williams winced slightly after jumping to hit an overhead in the third game of the second set and called the trainer out again to retape the ankle during the changeover, leading 3-0.
She dominated the second set despite the injury, allowing the Romanian player to win just six points.
Murray beat Haase 6-3, 6-1, 6-3 in the opening round and was asked what it felt like to play after his triumph at the U.S. Open, where he became the first British man since 1936 to win a major title.
"I can try and focus on the second part of my career now," he said.
The 25-year-old Murray seemed more at ease and relaxed than he has been in previous trips to the season's first major.
"It was a good start, nice to win in straight sets," he said. "It was the hottest day we've had for a while so the court was playing much quicker."
It's been 12 months since Murray started working with eight-time major winner Ivan Lendl, and he attributes much of the success in his breakthrough 2012 to his partnership with his new coach.
It's relaxed "in front of the cameras, yeah," Murray joked. "Behind closed doors he works me very hard.
"We've had a very good relationship so far. He's very honest, very open. He doesn't lie to you, he tells you exactly how it is and that's exactly what I needed."
In early women's matches Tuesday, 42-year-old Kimiko Date-Krumm upset No. 12-seeded Nadia Petrova of Russia 6-2, 6-0 to become the oldest woman to win a singles match at the Australian Open. Former No. 1-ranked Caroline Wozniacki won the last six games to beat Sabine Lisicki of Germany 2-6, 6-3, 6-3.
Former US Open and French Open champion Svetlana Kuznetsova continued her comeback from a knee injury that kept her out of the U.S. Open, ending her run of 40 consecutive majors. Also, No. 14 Maria Kirilenko had a 6-4, 6-2 win over American Vania King, and China's Peng Shuai beat Canada's Rebecca Marino 6-3, 6-0.