Melbourne:
With one former women's No. 1 making an early exit and the current one not playing until Tuesday, it was just as well that Kim Clijsters came back to give the Australian Open some first-day luster on a rainy, dreary day at Melbourne Park.
Former top-ranked Maria Sharapova was a surprise 7-6 (4), 3-6, 6-4 loser Monday to fellow Russian Maria Kirilenko. U.S. Open champion Clijsters, also a former No. 1 and making a return to the Australian Open after coming back from retirement, easily won her first-round match 6-0, 6-4 over Canadian qualifier Valerie Tetreault.
It was Sharapova's earliest exit from a Grand Slam since the 2003 French Open, and comes after she lost in the second round at last year's U.S. Open.
Top-seeded Serena Williams starts her title defense Tuesday against Urszula Radwanksa of Poland.
Another former No. 1 also on the comeback trail, seven-time Grand Slam singles winner Justine Henin, played her first-round match later Monday, as did No. 2 men's seed and defending champion Rafael Nadal.
Showers first delayed the start of play on outside courts Monday, then forced several suspensions during the day. The first match on Court 6 didn't finish until nearly seven hours after it started.
Clijsters, who won the U.S. Open in September in only her third tournament back from time off to get married and have a baby, is now six tournaments into her comeback, but still feeling the nerves that come with Grand Slam tournaments.
"I have the experience from the past, but I haven't been here for so long," Clijsters said. "So I think that's why it all feels new again. So, yeah, the butterflies are there, but they're not the same butterflies as the ones when I was 15 where I couldn't sleep the night before a match."
There were no nerves _ "just a bad day" _ said Sharapova, who was making her first appearance on Rod Laver Arena since winning the 2008 trophy. She missed the Australian Open last year as part of a 10-month layoff due to shoulder surgery, but said her shoulder did not bother her Monday.
"I could be disappointed or I could just take it as it is and just go back on the court and just keep working," said Sharapova. "I choose option two. A bad day's not going to stop me from doing what I love. I'll be back here on a Saturday of the second week, so you watch."
Sharapova rallied from 5-2 down in the deciding set, holding serve and then breaking Kirilenko to stay in the match. She dropped her own serve after giving Kirilenko double match point.
"It's never easy. I'm good friends with Maria," Kirilenko said, but "I tried my best to win today _ I came here quite confident."
In other women's play, last year's finalist, second-seeded Dinara Safina, won her first-round match, beating Magdalena Rybarikova of Slovakia 6-4, 6-4. Another Russian, No. 3 and French Open champion Svetlana Kuznetsova, beat Anastasia Rodionova of Australia 6-1, 6-2.
Yanina Wickmayer, playing again after having a suspension lifted by a Belgian court, beat Alexandra Dulgheru 1-6, 7-5, 10-8 in a 3-hour, 20-minute match that was interrupted by rain several times.
Despite her No. 16 ranking, Wickmayer had to qualify for the Australian Open because she was subject to a suspension _ later overturned _ for violating the World Anti-Doping Agency's "whereabouts rule" when entries for the season's first major closed.
In first-round men's matches, US Open champion Juan Martin del Potro beat American Michael Russell 6-4, 6-4, 3-6, 6-2 and No. 5 Andy Murray defeated South Africa's Kevin Anderson 6-1, 6-1, 6-2.
"Little bit weird playing under the roof here _ first time I've done it," Murray said.
Officials later reopened the roof at Rod Laver Arena, only to have rain pelt down on the court just before Nadal was scheduled to play his match against Australia's Peter Luczak, delaying the start by a half-hour.
Seventh-seeded Andy Roddick also sat through a needless rain suspension before beating Thiemo de Bakker of the Netherlands 6-1, 6-4, 6-4. The match at Hisense Arena, the tournament's second covered court, was suspended at 2-2 in second set so that organizers could close the roof, which had also been opened despite rain in the area.
"First rounds are always a little uncomfortable, especially at a Slam," Roddick said. "You're kind of built up, you're maybe a little bit overanxious. But I thought it was all right."
Elsewhere, No. 11 Fernando Gonzalez of Chile beat Olivier Rochus of Belgium 6-3, 6-4, 3-6, 6-1 and Croatia's Ivo Karlovic defeated No. 13 Radek Stepanek of the Czech Republic 2-6, 7-6 (5), 6-4, 3-6, 6-4. American Wayne Odesnik beat Slovenian qualifier Blaz Kavcic 4-6, 6-1, 6-4, 6-2.
Top-seeded Roger Federer was scheduled to play his first-round match Tuesday against Russia's Igor Andreev. Rain is again in the forecast.
Police ejected 11 people from Melbourne Park on Monday for disruptive behavior and smuggling flares onto the grounds. A group of Croatian supporters were also denied entry after setting off a flare.