Top scorer Adam Rooney has been ruled out until mid-April after suffering a thigh injury.
The loss of their 19-goal top-scorer has compounded the news that influential winger Jonny Hayes will also miss several games with a hamstring injury.
But McInnes has challenged Simon Church to continue his scoring form after handing him the responsibility of leading Aberdeen's attack.
McInnes said before the midweek game with Dundee Utd: "What do you do when you lose key players? You either roll up and feel sorry for yourself and have a victim's mentality, thinking, 'Poor us, poor us' - or you see it as someone else's opportunity.
"I'm delighted we've got Simon Church on the books. He's got two goals in four games and if he can keep that ratio up he will be doing well.
"It's the sort of thing we've been used to with Adam and of course we'd rather have Adam fit. There's not many teams - if any - who wouldn't want him in their side.
"But we will have to deal with it, as we have before. We've had to come to terms with it on Thursday when we realised he wasn't going to be available for us.
"We have to make sure that little things like injuries, pitches being poor or referees' decisions don't stop us doing what we want to do.
"We've got 11 games left and it's important we demonstrate how much those 33 points mean to us."
Source: Sporting Life