The British Amateur Rugby League Association side began their tour with a two-point win over West Fiji last week.
A scheduled game against Fiji Bati Residents on Saturday was called off on player welfare grounds - because of high heat and humidity - and captain Jamie Fields said the Lions are raring to go.
“It will be the first time I’ll have played the Aussies and something I am relishing,” said the Hunslet Club Parkside prop.
“I said to the lads they think they have a god-given right to win every game they play.
“That’s something I want to take away from them and I’ll be doing my utmost to get in their faces.
“We know that we are up against it, that’s why we are all here and are really chomping at it.”
Despite the sapping conditions Fields added: “Captain’s run went really well.
“I think we executed things a lot better than we have been doing.
“I think training in the late afternoon, at half past five, was an absolute godsend. The heat at previous training sessions has been intense.
“I’m more than happy with [the training session] – we did eight to 10 sets in good ball areas and not many, if any, went down.
“Slowly now, individuals are starting to move collectively and partnerships are developing, certainly our six and seven and Ian Jackson linking in from full-back.”
The game against the Aussies will kick off at 4.30pm local time, 3.30am in the UK.