Head coach Eddie Jones on Friday named Skelton in his starting line-up for the Pool C clash in Saint Etienne on Sunday, even though the lock limping out of training the day before with a calf injury.
Skelton was also missing from the official team photograph on Saturday, with Richie Arnold, who was originally named on the bench, wearing his No 5 jersey, and Matt Philip included even though he was not part of the original 23-man matchday squad.
"There's no mind games, we're just giving him as long as possible to get ready," said Palmer at the Geoffroy-Guichard stadium, where Australia and Fiji both took part in the traditional eve-of-match training sessions.
"He's an important part of our team and we're prepared to do that."
Palmer confirmed that hooker David Porecki would captain the side if Skelton missed out.
Skelton skipped the official photograph because he was undergoing treatment on his calf with the Wallaby physios, said Palmer.
Palmer batted away a question about why Philip had been included in the team photograph.
"He (Skelton) might play and he might not, so if he doesn't we're confident MP (Philip) can step up and do a job for us," said Palmer, a former international prop.
"He's a world class lock so he'll be Will's replacement if Will's not ready."
Skelton, 31, was a surprise choice as captain for the World Cup, after Jones left veteran flanker Michael Hooper out of his 33-man tournament squad.
Jones was evasive on Friday about Skelton, saying only that the New Zealand-born lock of Samoan descent would be given "right up until kick-off" to prove his fitness.
Jones recalled 34-year-old prop James Slipper to his starting line-up to replace the injured Taniela Tupou at tighthead.
Although Slipper will become only the third Wallaby after George Gregan and Adam Ashley-Cooper to appear in four World Cups, the prop was overlooked for the captaincy role.
But Jones said it was no disappointment as Slipper has always been a "team first" player.
"Dave, given the opportunity, he'll be superb with the way he goes about his business on the field as a player," said Slipper, who will win his 132nd cap on Sunday, a figure bettered for Australia only by Gregan's 139 test appearances.
"He leads by example, he's just one of those players who's really measured, really calm and composed, really world class at his craft, that hooker role.
"He's got the respect from the boys so if he's given the chance he'd do really well."
