Rain has halted play on the outside courts early on day one of the Australian Open just as local hope Omar Jasika was threatening to turn the tide against Hugo Gaston.

Frenchman Gaston raced through the first set 6-2.

But 27-year-old wildcard Jasika created six break-point opportunities — none of which he was able to convert — in the second game of the second set before play was suspended due to rain on Sunday with the pair locked at deuce.

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The action was continuing under closed roofs on the three main show courts.

Organisers issued a brief statement on social media confirming play on the outside courts would not resume for nearly two hours at best, and later said 3pm was the earliest possible resumption.

The delays will almost certainly expand the Monday and Tuesday schedules, which had eased with the use of a Sunday start for the first time.

Jasika shot to prominence in 2014 when he became the first player in 28 years to win the boys’ singles and doubles titles at the US Open.

The Australian has won only one of his four previous main-draw grand slam singles matches — and that was way back at the 2016 Australian Open.

Gaston lost his only previous clash with a local at the Australian Open, beating Christopher O’Connell in the opening round in 2022.

Jasika is one of five Australians in action on day one at Melbourne Park along with Adam Walton, Aleksandar Vukic, Li Tu and Daria Saville.

Two-time defending women’s champion Aryna Sabalenka from Belarus begins her title defence on Rod Laver Arena on Sunday evening against American Sloane Stephens, the 2017 US Open title-winner,

Other big names in action on day one include men’s No.2 seed Alexander Zverev from Germany and sixth-seeded Norwegian Casper Ruud.

– with 7NEWS