Essendon have suffered a major blow ahead of Sunday's AFL match against arch-rivals Carlton, with Mark Baguley a late withdrawal.
The Bombers announced on Saturday that Martin Gleeson, originally dropped for the MCG match, would take the vice-captain's place.
There was no immediate word on why the defender, one of Essendon's best players, was out of the team.
The makeshift Bombers can ill-afford to lose a player of Baguley's quality, especially in the wake of their horror first half on Anzac Day against Collingwood.
Given the nature of Essendon's team, they were always going to have poor performances - but the timing could not have been worse.
Not only was it their biggest stage for this season but, the day before, the rebuilding Blues were outstanding.
Carlton had their first win under coach Brendon Bolton when they upset Fremantle at Subiaco.
But Essendon coach John Worsfold's attitude can be summed up as "bring it on".
"I don't want to ever play a game of footy thinking 'we won that because the opposition weren't ready for us, or they were not switched on'," he said earlier this week.
"We want to take on teams like Collingwood who (on Monday) were coming out, backs to the wall, and see how good we are against that.
"Come out, throw everything at us, and we want to match up to that."
But Worsfold admitted they would have to rally, with Anzac Day a massive letdown after an encouraging start to the season.
"The aim is that we don't now think 'aw, it's a long, tough year - let's go through the motions'," he said.
"No way - we want to compete unbelievably hard, week-in, week-out.
"So that's the challenge."
One major item of good news this week for Essendon has been banned key defender Cale Hooker re-signing.
Of their 12 players serving doping suspensions, the speculation around his future had been strongest.
"If I can keep this group up where we don't need re-signings to say our morale is up, that's my aim," Worsfold said.
"These things are just a bonus and great news for us all."
Baguley's withdrawal means four changes for Essendon, with James Polkinghorne making his Bombers debut and Jonathan Simpkin and Ryan Crowley recalled.
Dennis Armfield and Nick Graham are back for the Blues.
Collingwood destroyed Essendon early with massive defensive pressure - a point not lost on Bolton.
"We do know if they get the ball in their hands, they can fast transition out of defence and through the middle," he said.
"Defensively, we're going to need to be on again."
It looms as a game of defence, with Carlton and Essendon the two lowest-scoring teams after five rounds.