Serena Williams of the US returns a ball during the first round match against Jarmila Gajdosova of Australia in the women's singles in the Australia Open Tennis Tournament at Rod Laver Arena Jan. 14, 2008. Serena Williams won 2-0 (6-3,6-3).--Xinhua

Serena Williams found her form quickly and overpowered Jarmila Gajdosova 6-3, 6-3 on Monday in the first match in the Australian Open.

Last year, Williams was unseeded, ranked 81st and coming off one of her worst losses on tour—in a Tier 4 event at Hobart—yet she beat six seeded players en route to the title at Melbourne Park. It was her eighth, and least expected, Grand Slam win. "It's obviously a lot different—I'm not No. 81 any more," Williams told the crowd after her 62-minute match at Rod Laver Arena against wild-card entry Gajdosova, a Slovak representing Australia.

Two former champions who were absent last year advanced to the second round this time. Top-ranked Justine Henin beat Japan's Aiko Nakamura 6-2, 6-2, while 2000 winner Linsday Davenport took three sets to top Italy’s Sara Errani 6-2, 3-6, 7-5 to set up a second-round match with last year's runner-up Maria Sharapova, a 6-4, 6-3 winner over Jelena Kostanic Tosic. Davenport, who passed Steffi Graf atop the all-time list of money winners on the women's tour at 21,897,501 U.S. dollars with the win, had it only marginally easier in the first round than third-seeded Jelena Jankovic, who saved three match points to edge Austria's Tamira Paszek 2-6, 6-2, 12-10.

Henin had to retire from the 2006 final against Amelie Mauresmo with stomach cramps. In her first match at Melbourne Park since then, she took the last six games against Nakamura to notch her 29th consecutive win.

Mauresmo, who has slumped from No. 1 to No. 18 since then, opened with a 6-7 (6), 6-0, 6-0 over Tatiana Poutchek of Belarus.

Henin was going through a divorce and skipped the last Australian Open, then came back to win the French and U.S. Opens and the season-ending championship. Her only loss in six months was to Marion Bartoli in the Wimbledon semifinals.