McVeigh has spent two nights in hospital with a blood infection stemming from a cut on his arm.
Coach Matthew Knights said the onballer, who as of Tuesday morning was “still struggling a little bit”, would be monitored in the lead-up to Saturday night's must-win clash with arch-rival Carlton.
“It's probably tough to say at the moment,” Knights said from Windy Hill.
“If he stays in hospital for another day or two he'd probably be unlikely, but if he gets out this afternoon, we'll have a look at it.”
In better news for Essendon, defender Nathan Lovett-Murray is available after missing the opening two games through suspension and the coach indicated he would return to the side.
However there won’t be wholesale changes for what the coach admitted was an important game after losing its opening two fixtures.
While predicting some changes for the clash against the Blues, Knights backed his players and his side's game plan in the wake of some criticism, most notably from Matthew Lloyd.
The retired spearhead addressed the team before Sunday's clash with Fremantle and said after the loss that the Bombers' style of play could not win a premiership.
Knights, who himself labeled the team's performance “pedestrian” after the match, said he was unaware of Lloyd’s opinions but his club believed it was on the right track for future success.
And the coach thinks he has the players at his disposal to achieve that success.
“We feel in the VFL at the moment we’ve got some really capable young men,” he said.
“But I also believe the guys in the team at the moment have got what it takes to continue to move this club forward and further, so I’ve got strong belief in this playing list that they are going to be capable of very good things in the future.
“I’ll always have that belief. It’s one of my philosophies of coaching - to always back your players.
“I’ll continue to do that. That won’t mean that we won’t have some genuine conversations at times about our responsibilities and our willingness as a team to be better … but I’ve got a belief in the playing group, yes.”
He said the Bombers had played good football for three quarters less than a fortnight ago against reigning premier, Geelong.
That gave him confidence of being able to turn it around against the Blues this weekend, despite his team straying from its customary quick play-ons and dynamic ball movement against Fremantle at Etihad Stadium on Sunday.
“We went away from what we're good at at the weekend and look what happens,” Knights said.
“So we don’t want to go away from our strengths.”
