McVeigh, 28, is progressing well in his recovery from a pre-season ankle injury, but Knights won't rush the important onballer.
"He trained well yesterday and did most of the session, but I went and had a chat to him after training and he just thinks he needs another week of conditioning," Knights said on Wednesday.
"He's pretty happy with his ankle, but we've got to make sure that McVeigh is right for the whole year. It's not just about this week and I would say, barring anything going wrong, he's a virtual certainty for the week after."
The last two encounters between the teams yielded a total of 89 goals and ended in wins to the Bombers.
Knights said he was happy for Saturday night's match to be another free-flowing affair, despite the indifferent early season form of key forwards Matthew Lloyd and Scott Lucas who have kicked two goals between them so far this season.
"Matthew Lloyd is as comfortable and relaxed as I've ever seen him. He's really pleased with where the club's headed. He wants this club to be successful more than anyone … He hasn't kicked a goal yet, but I felt his first quarter last week helped set the scene.
"Scott's a very proud man and he has been very frustrated with his own form, but the injury he had was a really tough injury for a tall forward or a ruckman.
"Physically, he is still finding his feet … but we've just got to stay supportive knowing that he's one of those who is capable of kicking three or four goals in a quarter."
At the other end of the ground in-form Blues' forward Brendan Fevola looms as a potential game breaker.
"I guess there's a lot of talk that Fev actually enjoys playing Essendon and he's had good success against us, but it becomes a team mentality I think," Knights said of his approach to curbing the prolific forward.
"It's really difficult [for one person] to stop a player like Fevola, or any good forward really, if the ball's coming down with really good service. It's the responsibility of the whole playing group to make sure that Fev doesn't get hold of us as he has done previously.
The Bombers are heavy outsiders with bookmakers, but Knights backed his young side to rise to the occasion.
"We see it as a real opportunity for us to be a part of something really big on Saturday night," he said.
"I know our young players are really looking forward to that."
