St Kilda have been boosted by the return of skipper Jarryn Geary for their clash with Carlton, but the Saints have played it safe with midfielder Zak Jones.
Coach Brett Ratten initially rated Jones a 50-50 chance to play after he reported some hamstring tightness in last week's win over Richmond.
But when the AFL moved their game against the Blues at Marvel Stadium from Saturday night to Thursday evening, the shorter five-day break was considered too much of a risk to take with Jones.
The league was forced to rejig the round-five fixture due to COVID-19 measures imposed by the Queensland government.
Geary will return after suffering a hamstring injury in round two against Western Bulldogs, with the seventh-placed Saints looking to improve to a 3-2 record.
The veteran defender was redeployed up forward against the Dogs, playing a defensive role on playmaker Jason Johannisen.
Ratten didn't rule out using Geary in a similar role against Carlton co-captain Sam Docherty, who was a key factor in the Blues' tight win over Essendon with 31 disposals and eight rebound 50s.
"We've got to have a look at where he fits for us ... he's been a back man most of his career," Ratten said on Wednesday.
"It was a strategy (tagging Johannisen) that we thought would work on the day, but Docherty's a different player to JJ, so does that work? I'm not sure.
"We'll go through that with finer detail after this training session."
Ratten is unfazed by the shorter break and is pleased his young side will have the opportunity to play on the big stage of a stand alone Thursday night fixture.
"It's all above the shoulders really ... it's not about the physical side of it," he said.
"Carlton are on the same break.
"It's good for our players to get into prime time on a Thursday night on free-to-air (television)."
The Blues regained Harry McKay, who missed last week's narrow win over Essendon with sore ribs, and Zac Fisher, who has overcome a syndesmosis injury.
Jack Silvagni will miss the match after suffering a bruised lung in an incident that saw Bombers star Zach Merrett suspended for a week.
Sam Philp was dropped after making his AFL debut against Essendon.