Americans Gauff, Pegula off at a canter at Australian Open

In-form Americans Jessica Pegula and Coco Gauff wasted little time in racing into the second round of the Australian Open on the opening day, briskly swatting aside their opponents in bright sunshine on Monday.

Pegula, seeded third behind Iga Swiatek and Ons Jabeur, hit her stride early in the new season by helping the US win the inaugural United Cup and took less than an hour to see off Jaqueline Cristian 6-0 6-1.

The 28-year-old simply overpowered her Romanian opponent and there were loud cheers from the Margaret Court Arena crowd when Cristian held serve in the second set to avoid the dreaded 'double bagel'.

“It definitely gives me a lot of confidence winning matches like that, knowing I'm playing really focused every single point and not letting any kind of points or games go to waste,” said Pegula.

“Definitely first matches are always really tough, especially at a slam, there's so much hype and anxious nerves leading up. So I'm glad it just went very smooth.”

Victoria Azarenka confessed to some nerves before coming through a tough first-round battle against Sofia Kenin 6-4 7-6(3) on Monday to ensure she would be the only former Australian Open champion remaining in the women's draw.

The 33-year-old Belarusian, champion in 2012 and 2013, said she had been concerned at playing Kenin even if the American had suffered an appalling run of injuries since she won her first Grand Slam at Melbourne Park in 2020.

“She's an amazing champion, I know she's had some injuries but she has the experience and I knew it was going to be a tough match,” the 24th seed said after the two-hour struggle.

Danielle Collins, runner up to Ash Barty at Melbourne Park last year, had an injury timeout for a knee issue before grinding out a 7-5 5-7 6-4 win over Anna Kalinskaya.

Amanda Anisimova was unable to continue the good start for American women at the first Grand Slam since Serena Williams hung up her racket, the 28th seed tumbling out 6-3 6-4 at the hands of Ukrainian Marta Kostyuk.

With Barty and Williams both retired, and twice champion Naomi Osaka pregnant with her first child, Melbourne Park will almost certainly crown a first-time women's champion this year.

There were convincing early wins on Monday for two former US Open champions who have been unable to build on their Grand Slam success.

Canadian Bianca Andreescu, the 2020 champion at Flushing Meadows, beat Marie Bouzkova 6-2 6-4, while 2021 winner Emma Raducanu made light work of Tamara Korpatsch in a 6-3 6-2 victory.

Briton Raducanu, now 20, will next face teenager Gauff, who came into the year's first Grand Slam on the back of a title win in Auckland and confirmed her good form with a 6-1 6-4 win over Katerina Siniakova on Rod Laver Arena.

Greek sixth seed Maria Sakkari also had a straightforward 6-1 6-4 win over China's Yuan Yue to set up a tie against Russian qualifier Diana Shnaider.

Italian 15th seed Jannik Sinner, a quarterfinalist last year, was the first man to reach the second round, rolling over Briton Kyle Edmund 6-4 6-0 6-2 on John Cain Arena.

Polish 10th seed Hubert Hurkacz joined him with a 7-1(1) 6-2 6-2 win over Spain's Pedro Martinez.

Top seeds Swiatek and Rafa Nadal open their campaigns in the evening session at Melbourne Park.