Williamson and co still under cloud: Latham

New Zealand have made an eleventh hour call to uncapped batsman Glenn Phillips for the Sydney Test as two of their star batsmen battle illness on the eve of the match.

Skipper Kane Williamson and left-hander Henry Nicholls were too unwell to train on Wednesday and Thursday, while spinner Mitchell Santner – who was facing the axe regardless after an ineffectual start to the series – has also fallen ill.

So right-hander Phillips, who has played 11 T20s for his country, has made a last-minute flight across the Tasman as cover for the ill batting duo.

The 23-year-old scored 116 for New Zealand A against a Test-quality England side six weeks ago, his fourth first-class century in 23 matches.

"We've obviously got a few balls up in the air at the moment and we want to be on the safe side and have options," said NZ coach Gary Stead.

"Glenn has been in terrific form this season and has good versatility with where he can bat and the roles he can play.

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"He's been around the Black Caps T20 team for the past couple of years so should feel comfortable in the environment.

"We're still hopeful Henry and Kane will pull through and we will give them every chance to prove their fitness.

"If one or both are ruled out then we will consider our options and most importantly how they balance the side for this final Test."

Tom Latham, who filled in for Williamson at the Prime Minister's reception on New Year's Day then performed pre-match press duties, suggested it would take a lot to keep his skipper out of the final XI on Friday.

"He's a great leader," Latham said of Williamson. "If there's any chance of him playing, even if it's a small chance, he'll certainly be playing.

"Obviously it's up in the air. A couple of boys are a little bit crook unfortunately. Fingers crossed they'll be right ... hopefully nobody else catches it."

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Latham and veteran paceman Tim Southee have both captained in ODI cricket, while Ross Taylor was ousted as skipper in favour of Brendon McCullum back in 2012.

Southee was slated to lead in Williamson's injury-enforced absence last year but that Test was cancelled because of the Christchurch mosque attacks.

Latham was unsure who would captain his team if Williamson didn't take the field.

"All those conversations are up in the air," he said. "We have many leaders among the group.

"I'm sure the decisions will be made later on today or in the morning."

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Jeet Raval is the only reserve batsman in the touring party and was dropped for the second Test having averaged 7.3 in his past nine Test innings.

"I'm sure we'll have a few options depending on who's right and who's not," Latham added.

The Black Caps were initially upbeat Williamson, who has struggled this series but is comfortably their best batsman, would train on match eve.

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)