Williamson and co still under cloud: Latham

For the second straight day New Zealand captain Kane Williamson was unable to train at the SCG due to illness and is racing against the clock to be fully fit for the third Domain Test.

Williamson is suffering from flu-like symptoms and has been quarantined from the Black Caps squad with less than 24 hours until the first ball of the series finale in Sydney.

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Williamson and middle-order batter Henry Nicholls have missed the past two days of training while left-arm orthodox spinner Mitchell Santner has also pulled up unwell and did not practice on Thursday.

Opening batter Tom Latham filled Williamson's shoes in the captain's pre-match press conference and said it would take a lot for his skipper to miss the New Year's Test with pride and World Test Championship points on the line having already lost the series.

"He's obviously a great leader amongst this group and he's passionate about this group," Latham said.

"If there's any chance of him paying, even if it's a small chance, he'll certainly be playing.

"It's gone around the team a little bit which isn't ideal, but fingers crossed they're resting up today and hopefully they'll wake up in the morning and be good to go."

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Losing Williamson, the No.3-ranked Test batter in the world, to illness would be a hammer blow to the tourists despite the visiting skipper's lean campaign.

In four innings this series he's scored just 57 runs and was out in both innings at the MCG to tearaway quick James Pattinson.

Despite the uncertainty around his participation in the annual Pink Test, Australia captain Tim Paine is expecting his counterpart to be taking the field on Friday.

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"We're planning for him to play and I think if Kane Williamson misses a couple of days’ training I don’t think it's going to affect him too much," Paine said today.

"A player of his quality knows what he is doing. He knows how to prepare himself and how to get himself up for big games.

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"We're preparing for the best of Kane Williamson and if he’s not there then we saw last game, a guy like Tom Blundell can come in and take it right up to us so we know they've got some very good players.

"We're not sure what XI they’re going to go with but what we've done is prepare ourselves and looked really closely at all their players they've got here.

"We're prepared for everyone of them."

Should Williamson and Nicholls be ruled out, reserve batter Jeet Raval, who was dropped after the first Test, would return, while leg-spinner Todd Astle, who has two first-class centuries, could be included.

Whoever takes the field for the Black Caps, Latham – Williamson's likely replacement as skipper if unavailable – is confident in his squad to compete with a red-hot Australian side.

"If we lost those guys it would be a little bit disappointing, but I know we've got a squad of 15 here that are passionate about this team and whatever side we do end up playing we've got the backing of the whole group that it's the right team that to go out and do the job," Latham said.

"We haven't necessarily played our best brand of cricket since we've been over here.

"I know the guys are really excited about getting out there over the next five days and putting in a good performance on the board."

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Domain Test Series v New Zealand

Australia squad: David Warner, Joe Burns, Marnus Labuschagne, Steve Smith, Matthew Wade, Travis Head, Tim Paine (c, wk), Pat Cummins, Mitch Starc, Nathan Lyon, James Pattinson, Michael Neser, Mitchell Swepson

New Zealand: Todd Astle, Tom Blundell, Trent Boult, Colin de Grandhomme, Matt Henry, Kyle Jamieson, Tom Latham, Henry Nicholls, Jeet Raval, Mitchell Santner, Tim Southee, Ross Taylor, BJ Watling, Neil Wagner, Kane Williamson (c)

First Test: Australia won by 296 runs in Perth

Second Test: Australia won by 247 runs

Third Test: January 3-7, SCG (Seven, Fox & Kayo)