Novak Djokovic, Maria Sharapova and Venus Williams are among the big names to have won on day one of the Australian Open, while Britain's Heather Watson also booked her place in the second round.
Rod Laver Arena
Maria Sharapova (Rus)  beat Olga Puchkova (Rus) 6-0 6-0
Sharapova, in her first competitive match of 2013, showed no signs of rustiness by brushing aside her Russian countrywoman in 55 minutes. The French Open champion and last year's Australian Open runner-up missed the warm-up event in Brisbane after suffering a collarbone injury shortly before Christmas.
"I didn't want to focus on the fact I hadn't played a lot of matches, I just wanted to focus on what was ahead of me and really concentrate and be aggressive," said the 2008 champion.
Samantha Stosur (Aus)  beat Kai-Chen Chang (Tpe) 7-6 (7-3) 6-3
Stosur, the 2011 US Open champion, has only managed to reach the fourth round of her home Grand Slam twice in 10 appearances and struggled to assert herself in the first set before securing victory. The 28-year-old broke a run of five consecutive losses on home soil, including a first-round exit at the Australian Open in 2012.
"I desperately wanted to win out there today, but didn't necessarily feel it any more than my first rounds in Grand Slams," she said. "From here hopefully I can loosen up a little bit and keep playing better and better."
Novak Djokovic (Ser)  beat Paul-Henri Mathieu (Fra) 6-2 6-4 7-5
Djokovic's bid to make history at the Australian Open started impressively as the world number one swept aside the challenge of Mathieu. Djokovic is hoping to become the first man in the Open era to win three successive titles in Melbourne and looked in good form from the outset with an entertaining 6-2 6-4 7-5 win.
"It's great to be back in Melbourne, this is by far my most successful court in my Grand Slam career," said the three-time champion. "Twelve months ago I played a six-hour final here so it's amazing to be back."
Janko Tipsarevic (Ser)  beat Lleyton Hewitt (Aus) 6-7 5-7 3-6
Hewitt, unseeded but playing in a record 17th consecutive Australian Open, was knocked out by Serbian eighth seed Janko Tipsarevic after three hours of high-class tennis.
"Against quality players, you've got to take your chances, but to his credit Janko raised his level and played some great points," said Hewitt.
Ana Ivanovic (Ser)  beat Melinda Czink (Hun) 6-2 6-1
Venus Williams (US)  beat Galina Voskoboeva (Kaz) 6-1 6-0
Williams took the first step towards a potential third-round clash with Maria Sharapova by thrashing Voskoboeva. The 32-year-old Williams, who won her first tournament in almost three years in Luxembourg last October after battling injuries and illness, was too powerful for the 28-year-old.
"It's nice to spend less time on court and not be in long sets," said the American. "A win is a win no matter what it is, but it's nice when it's more routine."
Fernando Verdasco (Spa)  beat David Goffin (Bel) 6-3 3-6 4-6 6-3 6-4
Dominika Cibulkova (Svk)  beat Ashleigh Barty (Aus) 3-6 6-0 6-1
David Ferrer (Spa)  beat Olivier Rochus (Bel) 6-3 6-4 6-2
Margaret Court Arena
Li Na (Chn)  beat Sesil Karatantcheva (Kaz) 6-1 6-3
Agnieszka Radwanska (Pol)  beat Bojana Bobusic (Aus) 7-5 6-0
Radwanska, the winner of the warm-up events in Auckland and Sydney, looked in danger of dropping her first set of 2013 when Australian wildcard Bobusic served for the opener at 5-4 but the Pole upped her level and rattled off the next nine games to go through.
Mikhail Youzhny (Rus)  bt Matthew Ebden (Aus) 4-6 6-7 (0-7) 6-2 7-6 (7-4) 6-3
Madison Keys (US) beat Casey Dellacqua (Aus) 4-6 6-7
Marcos Baghdatis (Cyp)  beat Albert Ramos (Spa) 6-7 (0-7) 7-6 (7-4) 6-4 3-6 6-3
Heather Watson (GB) beat Alexandra Cadantu (Rom) 2-6 6-3 6-2
Andy Murray, Jamie Baker and Laura Robson play on Tuesday.
Stats of the day
Nicolas Almagro leads the serving charts with 34 aces in his five-set win over Steve Johnson
Poland's Jerzy Janowicz hit the fastest serve of day one at 141.7mph (228kph)
American Coco Vandeweghe topped the women's charts at 119.3mph (196kph)
Edouard Roger-Vasselin's win over Ruben Bemelmans was the longest match of the day at 4hrs 25mins