Tigers coach Damien Hardwick would not elaborate on the extent of Deledio's injury, but it is believed he is dealing with an ankle complaint.
"He's a wait and see. We'll see how he trains today. He's an important player, so we'll give him up until the last minute to see how he goes," Hardwick said.
The fact Deledio joined the 'slips cordon' at training alongside rehab group players including Alex Rance and Ivan Maric, does not exactly engender confidence in his availability for this week's game.
The Tigers star was limited in his movement, mainly standing still as the players worked on their reflexes by catching tennis balls hit by one of the club's assistant coaches.
Reigning best and fairest winner Daniel Jackson should soften the blow of Deledio's likely absence, with the midfielder almost certain to return this week against the Dogs.
Jackson has played two VFL matches since shaking off the effects of a hamstring injury and won 15 possessions when playing for the VFL Tigers at the weekend.
"He's an important player for us and his leadership around the ground is enormous, so we're really looking forward to welcoming him back in," Hardwick said.
Hardwick believes Jackson's impending return will complement the "fantastic" role Matt Thomas has been playing for the Tigers.
"Now we get two battering rams in there which is always handy, so now we've got two guys who are contested ball winners," Hardwick said.
"It probably helps Cotch out a little bit as well to get a bit of protection in there for him."
The Tigers coach was full of praise for Thomas, who has excelled in the midfield after being elevated off the club's rookie list prior to the season.
"The thing that makes him a good player is he does the simple things well," Hardwick said.
Rance, who fractured his foot after falling off an exercise bike during a cross-training session in a freak accident, is two to three weeks away, according to Hardwick.
The Tigers defender was walking around in a moon boot prior to training on Thursday.
Despite the loss of some key players, Hardwick said there was no excuse for poor performances with some crucial games coming up in the schedule.
The Bulldogs game is followed by a four-week block which includes clashes against top-four aspirants Collingwood, Hawthorn and Geelong.
"We're probably playing at about a 6/10 at the moment. But we'll be ok, we'll get our game up and going and we'll go from there.
"The thing is we just need to continue to do the little things well. We probably haven't been playing our best footy, but the quality sides win games when they're not playing well, which is what we are."
Twitter: @AFL_BenGuthrie