Both sides are looking to move into, and then stay in the play off places. But both sides, along with most of the other play off chasers, are inconsistent.
“This game against Birmingham is as important as the seven games that come after it," Mackay said.
“It’s no less or more important than any of those. They are up there and around the same position as us.
“I think their result against Portsmouth on Tuesday, coupled with ours against Coventry, highlights the inconsistency of teams in this division.
“We have to hold our nerve and stay calm now.
“Certainly at West Ham, Southampton and Brighton earlier this season we’ve done well.
“St Andrew’s has never been an easy place to go and it is going to be tough.”