World No.3 Jessica Pegula has wasted no time stamping her title credentials by powering into the second round of the Australian Open early on day one at Melbourne Park.
The 28-year-old American was the day's first winner, needing just 59 minutes to see off the challenge of Romania's Jaqueline Cristian 6-0 6-1.
Pegula won the opening nine games on Margaret Court Arena and sealed the lopsided victory with an ace.
Her second-round opponent will be either Belarusian Aliaksandra Sasnovich or 15-year-old Czech wunderkind Brenda Fruhvirtova, who advanced through qualifying.
Pegula underlined her status as a genuine chance to win a maiden grand slam title at Melbourne Park by crushing world No.1 and title favourite Iga Swiatek in straight sets at the United Cup in Sydney in early January.
She reached the quarter-finals at her previous two Open campaigns and was beaten by eventual champ Ash Barty last year.
Seventh seed and fellow American Coco Gauff did it tougher, needing seven match points in a marathon final game before overcoming Czech Katerina Siniakova 6-1 6-4.
"I'm really pleased with that," said the 18-year-old Gauff.
"Katerina is a fighter. I knew that she was going to fight to the last point and she proved that today.
"We had some excellent points in that last game."
Gauff is unbeaten in 2023, having started her year with a title triumph at the ASB Classic in Auckland, which included a win over countrywoman and former Australian Open champ Sofia Kenin.
The teenager's win set up a blockbuster second-round encounter with British darling Emma Raducanu, a 6-3 6-2 winner over Germany's Tamara Korpatsch.
Greek sixth seed Maria Sakkari and 2022 finalist Danielle Collins also moved safely into the second round.
Sakkari outclassed China's Yue Yuan 6-1 6-4 to book a meeting on Wednesday with Russian qualifier Diana Shnaider.
Runner-up to Ash Barty last year, 13th-seeded Collins scraped past Anna Kalinskaya 7-5 5-7 6-4 in an early scare.
But her 28th-seeded American compatriot Amanda Anisimova became the first seeded casualty of the tournament, bowing out 6-3 6-4 to Ukraine's Marta Kostyuk.
No.25 Marie Bouskova from the Czech Republic also fell 6-2 6-4 at the first hurdle to Canada's 2019 US Open champ Bianca Andreescu.