MELBOURNE, Australia — With one former women's No. 1 making an early exit and the current one not playing until tomorrow, it was just as well that Kim Clijsters and Justine Henin 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 today to fellow Russian Maria Kirilenko.

U.S. Open champion Clijsters, also a former No. 1 and making a return to the Australian Open in her sixth tournament back from retirement, easily won her first-round match 6-0, 6-4 over Canadian qualifier Valerie Tetreault.

Later Monday, another former No. 1 also on the comeback trail, seven-time Grand Slam singles winner Justine Henin, advanced with a 6-4, 6-3 win over fellow Belgian Kirsten Flipkens. Henin lost to Clijsters in the Brisbane International final 10 days ago in her return to the tour.

Second-seeded Rafael Nadal, the defending men's champion, beat Australia's Peter Luczak 7-6 (0), 6-1, 6-4.

Nadal won his first Grand Slam singles title on hard courts — to go with his four at the French Open and his one Wimbledon title — when he beat Roger Federer in last year's final at Melbourne Park.

The Spanish left-hander didn't find his rhythm until the latter part of the first set against Luczak, dominating the tiebreaker and much of the remainder of the match.

"I'm always happy to win the first round of a Grand Slam," Nadal said. "Peter was playing really well in the first set but he made three errors in the tiebreak that helped me. I knew it was going to be a tough match."

Steady rain first delayed the start of play on outside courts, then forced several suspensions and more than a dozen postponements. Officials finally called off play at 10 p.m. on outside courts when the rain returned, forcing the matches to be concluded Tuesday.

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.

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, still feels the nerves that come with playing in a Grand Slam.

"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 ..."

There were no nerves — "just a bad day" — for 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," Sharapova said. "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."

Henin was mostly untroubled in beating Flipkens, getting a service break in the ninth game, then holding to take the set. Henin's trademark groundstrokes were on display, augmented by a number of forays to the net and a drop shot that Flipkens didn't come close to retrieving.

"I think it's the way I have to play if I am to get better on grass also in the future," Henin said of her time at the net. "And I think that when I put pressure, that's how I'm a better player."

Henin's next match is against fifth-seeded Elena Dementieva, who downed Vera Dushevina 6-2, 6-1.

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. Two other Russians also won — No. 3 and French Open champion Svetlana Kuznetsova beat Anastasia Rodionova of Australia 6-1, 6-2.

In other first-round men's matches, U.S. 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.

Seventh-seeded Andy Roddick beat Thiemo de Bakker of the Netherlands 6-1, 6-4, 6-4.

"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."

Another American, Mardy Fish, was beaten in his first-round match, losing 6-2, 1-6, 6-3, 6-3 to wild-card entry Andrey Golubev of Kazakhstan. 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.