All-rounder James Faulkner will miss the three-Test series due to a knee injury and Marsh looms as another pre-tour casualty with a calf problem.
The left-hander will not travel with the squad to South Africa on Wednesday to continue further treatment on an injury suffered in Sunday's fifth one-day international against England.
A decision on his fitness is set to be made "in due course" to create the possibility of Bailey, who played all five Ashes Tests, being handed a reprieve.
Bailey is preparing to lead Australia's Twenty20 team against England in a three-match series, starting in Hobart on Wednesday, but expects that is where he will remain.
The 31-year-old suggested Phil Hughes was a more likely starter when asked if he thought a late call-up might be forthcoming: "No, I wouldn't have thought so. I reckon Phil Hughes (will be selected)."
Australia's tour plans have been set back by the injuries, with seamer Jackson Bird also set to remain behind for a couple of days at least.
The right-armer will have a jarred back assessed in Hobart after he hurt it diving in the field during the Big Bash League last week.
Faulkner underwent surgery on Tuesday, but it is hoped he could return in time for the World Twenty20, which begins in Bangladesh on Marsh 16.
"James injured his knee during the Australia Day one-day international in Adelaide," physiotherapist Alex Kountouris said.
"He has had subsequent scans and was reviewed by Cricket Australia's medical team and a knee specialist, and will require arthroscopic surgery on Tuesday.
"James' exact rehab plan and return to training and playing will be determined after surgery but unfortunately for him, he will not be available for the upcoming Test tour of South Africa.
"We are hopeful that he will recover in time to play the Twenty 20 games on that tour and take part in the ICC World Twenty20."
Fellow all-rounder Moises Henriques has been called up in Faulkner's place and is set to play in Wednesday's Twenty20 before flying out.
"It is very unfortunate news for James but I guess that's the way cricket goes and to then get the call up to the Test tour is delightful," he said.
"I've got some big shoes to fill there. I'm an all-rounder as well so I'll come in and fill a similar sort of role."
The 26-year-old admits he is unlikely to play in the first Test, which begins at Centurion on February 12, but hopes to add to the three Test caps he won in India early last year.
"For the first Test barring injuries you'd assume it would be a very similar line-up after winning (the Ashes) 5-0," he said.
"It's a fantastic Test team. I've just got to make sure I'm doing all the work off the field that if there is a vacancy that I'm there ready to step up."
Henriques travelled with Australia A for their tour to South Africa and Zimbabwe last July and, having also toured India, believes he is starting to feel more at home in the green and gold.
"I think so. I feel like my batting has progressed over the last couple of years, or my cricket altogether," he said.
"I'm learning a lot more about the game and actually putting it into practice.
"When I was a bit younger I struggled to learn from mistakes and I feel like I'm learning quicker now.
"It will be tough (touring South Africa). It will be completely different conditions in South Africa so I'll have to learn on the go over there.
"Their bowling attack will be very different to the bowling attack that India threw at us in the Test series over there."
Henriques will at least have the lessons learned from the Australia A tour to fall back on, when he averaged 25.5 with the bat in two unofficial Tests.
"It was good to go over there and play in those conditions in the long form of the game," he said.
"I'd never played four-day cricket over there before until that tour.
"It was good to see how the wickets wear down over the constant battering of three and four days."