Australia are ready to launch their Women's T20 World Cup defence in baking Sharjah with competition for places in their all-conquering side just about as hot as the soaring temperatures in the UAE.

As they prepared for their opening match against Sri Lanka, who lost their first match to Pakistan at the same venue on Thursday, coach Shelley Nitschke admitted it was still a tough battle to grab a spot in the team with so many world-class operators in their squad.

Having had a good look at the low, slow Sharjah pitch, Australia were left with some big decisions, in particular about the composition of their bowling attack, before the Sri Lanka clash on Saturday.

Nitschke had encouraging reports about the fitness of brilliant young batter Phoebe Litchfield, who had missed their two warm-up matches with a groin injury, and Grace Harris, the ebullient allrounder who has also been sidelined with a calf strain.

The 21-year-old Litchfield looks certain to be included if fully fit, while big-hitting Harris's spin was also set to be a considerable asset if it's deemed she's not too rusty after missing the recent New Zealand series.

"Grace is on track, going well," said Nitschke, admitting should she be available for a match likely to be played on a spin-friendly track, it would add to any potential selection dilemmas.

"For sure. It's tough for spots, and we've got some really good players in our squad of 15, so I think there's certainly still some tough decisions that need to be made. We just need to see where that lands with Grace's fitness and whatnot."

That theme was taken up by Aussie allrounder Tahlia McGrath on Friday as she told reporters: "Spin played a really big role in the last two games in Sharjah, and it's always going to be a selection dilemma for us when you look at our 15 and see that every single player can play a role.

"The talent there is enormous."

The idea of a four-pronged spin attack could indeed prove irresistible after Thursday's two matches at Sharjah featured 22 wickets falling to the slow bowlers.

"That should guide us into which way we want to go there," Nitschke had noted before watching Thursday's action unfold there.

Australia's three-game sweep over New Zealand last month looks a particularly promising form guide, given how Sophie Devine's Kiwis outplayed India in their opening match on Friday.

Yet it also indicated Australia, going for a fourth straight title, are in a really demanding group.

Asia Cup champions Sri Lanka will see it as a must-win contest, with captain and star player Chamari Athapaththu not about to fail twice in a row after her early dismissal for six paved the way for the capitulation against Pakistan.

Australia will be looking for their own sharp start, with captain Alyssa Healy potentially leading from the front as she stands just 13 runs away from becoming the second Australian woman to score 3000 runs in women's T20Is after Meg Lanning (3405).