Marnus Labuschagne's World Cup dream appears shattered after being dropped from Australia's one-day side, while uncapped leg-spinner Tanveer Sangha and WA allrounder Aaron Hardie have bolted into the mix for the tournament to be played in India later this year.

Cricket Australia today named an extended 18-man squad for the ODI World Cup that will later be trimmed to 15, with a five-match series in South Africa in September the first assignment.

Selectors also named a new-look T20 squad with a strong Big Bash flavour for three matches in South Africa before the ODI World Cup build-up begins, with big names rested from the shortest format ahead of a gruelling one-day campaign.

Labuschagne is the most notable omission from the 50-over squad having played 30 of Australia's 38 matches since his debut in January 2020, with an average of 31.37.

Australia's ODI squad: Pat Cummins (c), Sean Abbott, Ashton Agar, Alex Carey, Nathan Ellis, Cameron Green, Aaron Hardie, Josh Hazlewood, Travis Head, Josh Inglis, Mitchell Marsh, Glenn Maxwell, Tanveer Sangha, Steve Smith, Mitchell Starc, Marcus Stoinis, David Warner, Adam Zampa 
* To be trimmed to 15 for the ODI World Cup

Pat Cummins was revealed to have a fractured wrist that will keep him sidelined for six weeks but will join the ODI squad in South Africa in preparation for a return to playing in India, where Australia have a three-game series in late September ahead of the World Cup.

Mitchell Starc is also recuperating from a shoulder injury picked up in the Ashes but has been cleared for the South Africa ODIs.

Cummins – Australia's ODI captain – has "an undisplaced fracture of his left radius which requires six weeks rehabilitation," said Australia's selection chair George Bailey.

"We view a period of enforced rest for Pat as a positive ahead of this important World Cup campaign. 

"There are still a number of games he could play before the World Cup which is more than enough for him to have a strong preparation." 

Selectors have not named a vice-captain for the ODI squad. Hazlewood skippered the team in one match against England last November, while Steve Smith took on the job for a three-match tour of India in March this year.

Sangha's selection is a real bolt from the blue – the 21-year-old has not played any top-level cricket since a one-day domestic practice match in Coffs Harbour last September, after which he was diagnosed with a back stress fracture that sidelined him for the entire 2022-23 summer.

Sangha had previously toured with Australia's T20 squad to New Zealand in February 2021, and while named in an extended squad for tours of the Caribbean and Bangladesh later that year, he ultimately did not make the touring party.

Glenn Maxwell will miss the ODI leg of the South Africa tour with the 34-year-old expecting the arrival of his first child, and will join the squad in India, where they are scheduled to play a three-match ODI series between September 22 and 27 with games in Mohali, Indore and Rajkot.

Official warm-up fixtures against yet-to-be-named opponents will follow before Australia will then meet India again in a blockbuster opener to their World Cup campaign proper, in Chennai on October 8.

Veteran David Warner and Travis Head look set to form a left-handed opening combination for Australia, although Mitch Marsh may remain an option after dominating as opener in Warner's absence during March's three-game tour of India.

Hardie's inclusion in the extended ODI squad shows how highly rated he is by selectors, having also been included in the T20 squad. While a T20 cap appears certain, the WA product will be vying with Marsh, Cameron Green, Marcus Stoinis and Sean Abbott to fill the seam-bowling allrounder spots with three players to be trimmed before the World Cup.

Ashton Agar joins Adam Zampa and Tanveer as spin bowlers in the squad, while noted death overs specialist Nathan Ellis joins familiar faces Cummins, Starc and Hazlewood as pace bowling options.

Jhye Richardson was not considered as he continues his recovery from a series of hamstring issues that have plagued him, while Lance Morris is on the comeback trail from a back issue.

"This side has been extremely impressive for several years in limited-overs cricket," said Bailey.

"There is an enormous amount of skill and experience in the group, which you need in a World Cup."

Selectors expect to trim the ODI squad to 15 in early September, but can make changes up until September 28, after which any changes require ICC approval.

Australia's run to the ODI World Cup

2023 Qantas Tour of South Africa

September 7: First ODI, Bloemfontein (D/N), 9pm AEST

September 9: Second ODI, Bloemfontein (D/N), 9pm AEST

September 12: Third ODI, Potchefstroom (D/N), 9pm AEST

September 15: Fourth ODI, Centurion (D/N), 9pm AEST

September 17: Fifth ODI, Johannesburg, 6pm AEST

2023 Qantas Tour of India

September 22: First ODI, Mohali (D/N), 6pm AEST

September 24: Second ODI, Indore (D/N), 6pm AEST

September 27: Third ODI, Rajkot (D/N), 6pm AEST

Australia's 2023 ODI World Cup fixtures

October 8: v India, Chennai (D/N), 7.30pm AEDT

October 12: v South Africa, Lucknow (D/N), 7.30pm AEDT

October 16: v Sri Lanka, Lucknow (D/N), 7.30pm AEDT

October 20: v Pakistan, Bengaluru (D/N), 7.30pm AEDT

October 25: v Netherlands, Delhi (D/N), 7.30pm AEDT

October 28: v New Zealand, Dharamsala, 4pm AEDT

November 4: v England, Ahmedabad (D/N), 7.30pm AEDT

November 7: v Afghanistan, Mumbai (D/N), 7.30pm AEDT

November 11: v Bangladesh, Pune, 4pm AEDT

Australia ODI squad: Pat Cummins (c), Sean Abbott, Ashton Agar, Alex Carey, Nathan Ellis, Cameron Green, Aaron Hardie, Josh Hazlewood, Travis Head, Josh Inglis, Mitchell Marsh, Glenn Maxwell, Tanveer Sangha, Steve Smith, Mitchell Starc, Marcus Stoinis, David Warner, Adam Zampa
* To be trimmed to 15 for the ODI World Cup