The midfielder has been sidelined since the opening day of the season - a 2-1 win over Kilmarnock - with a knee problem which required surgery.
He returned to training this week and McInnes has refused to rule out the possibility of Robson making his comeback this weekend.
He said: "It's early days. We've still got a couple of training sessions to get through before Saturday's game and we will see how he is.
"Certainly, since the start of the week, it's been very encouraging.
"You can't ignore a player of his experience and his quality in any game, never mind such a good game as the United game."
McInnes is looking for a positive response from his players following a 1-0 defeat to Ross Country in their last outing.
He said: "You always want to get a positive result going into the international break and, unfortunately for us, we didn't manage to do that.
"It's given us time to get one or two players back and, thankfully, everybody seems to have come back okay from international duty.
"We'll be ready for it. If the game was kicking off in an hour, it still wouldn't be soon enough. We want to get going now.
"It's set up for a good afternoon's work and hopefully, at the end of it, we've got three points in the bag."