Watch: Serena, Venus, Osaka cruise into Australian Open second round

With the win, Serena improved her flawless record in first-round matches at Grand Slam events to an astounding 76-1.

Melbourne: Serena Williams, in search for a record-tying 24th Grand Slam title, started her Australian Open campaign in an emphatic manner as she zipped past Laura Siegemund of Germany, 6-1, 6-1, on to notch her opening-round win on Monday.

With the win, the seven-time Australian Open champion improved her flawless record in first-round matches at Grand Slam events to an astounding 76-1.

Serena is contesting a milestone 20th Australian Open, and her 56-minute win over Siegemund was her 100th career match at the event.

"This was a good start. Definitely vintage 'Rena," the 39-year-old said after the match. "It's definitely good. I think I'm pretty good at pacing myself in a Grand Slam.

"Last year was very crazy for the world, and to be able to do what I love and to be able to come out and compete and play at a Grand Slam, after the last 12 months, it makes me appreciate the moment even more," she added.

The American will next face Serbia's Nina Stojanovic on Wednesday.

Earlier in the day, Serena's elder sister Venus also registered a straight-set win in her opening round contest, defeating Kirsten Flipkens of Belgium 7-5, 6-2, at the Margaret Court Arena.

Meanwhile, three-time Grand Slam champion Naomi Osaka defeated Russian Anastasia Pavlyuchenkova 6-1, 6-2 in her opening round contest which lasted 68 minutes at the Rod Laver Arena.

"I feel like for me the most recent memory I have of playing her was in the Osaka final (to win the title in 2019), so it's always really hard to play someone that good in the first round," Osaka said after the match.

She will next lock horns with former world number four Caroline Garcia from France, who overcame Slovenia's Polona Hercog, 7-6(6), 6-3.