Warner had hurt his neck during a fielding drill on Tuesday.
Subsequently, Glenn Maxwell has been called up to the squad as cover.
The uncertainty complicates what would otherwise be a straightforward selection for Australia on Thursday morning.
"Shaun Marsh has obviously got a bit of history with back injuries". But Marsh himself being under a cloud muddies those waters somewhat.
Hafiz Saeed released from house arrest
The counsel of the federal government argued that the release of four associates of Saeed had created law and order issues. The Pakistan government failed to provide any evidence to the court as for why Hafiz Saeed was kept under house arrest.
However, should Warner lose his fitness race, the hard-hitting Maxwell could slot into the middle order, with Marsh elevated to open alongside uncapped Western Australia team-mate Cameron Bancroft, Cricket Australia said.
Warner has a stiff neck after injuring it at training, while Marsh has been dealing with a back issue.
A day later, though, his captain said: "Davey's going well". "He had a hit just before".
"He's very confident and he says he'll be right to go", Smith said of Warner on Wednesday.
Irani takes on Congress over 'chaiwalla' meme
A controversy erupted over the tweet with users slamming the Congress for launching "derogatory" attack on the prime minister. Differences in policy and opinion aside, Congress culture imbibes respect for the PM and all political opponents".
Hugh Morris, Glamorgan's director of cricket, said: "We wanted to bring in someone who is experienced at worldwide level, can bat at the top of the order and can play in all three formats of the game, and Shaun ticks all of those boxes for us". Guys have injuries every now and then and have little niggles.
"He said he'll even bat like Shivnarine Chanderpaul if he has to and face the other way (laughs), so I think he'll be alright".
"There is a lot of exciting young talent at the club, and hopefully I can put in some good performances so we can bring some silverware to Wales".
Morrissey Defends Kevin Spacey; Says The Actor Is Being 'Attacked Unnecessarily'
Anthony Rapp broke decades of silence to allege Spacey made sexual advances towards him after a party in NY in 1986. That's why it does not sound very credible to me. "It seems to me that Spacey has been attacked unncessarily".
"It's the reason why Australia play the first Test of a series here all the time".