Bruce believes his own players were largely to blame for giving the Everton crowd a reason to get behind their team and roar them on to victory.
The home supporters were angry when, despite Birmingham substitute Garry O'Connor being on the ground with an injury, team-mate Mikael Forssell played on.
"I told Forssell he should have kicked the ball out when he had the chance. What happened then is that the home crowd got their backs up, they were annoyed with what happened and it sparked their team into action.
"Little things like that change matches. If we had kicked the ball out when we had the chance, they would have had to give it back to us and it would have calmed things down and taken up some time.
"But by doing what we did, and with Kapo then kicking the ball out for a throw-in deep in Everton's half, everybody was going berserk.
"Everton were being roared on and they came back at us to get those two goals in injury-time. All that could have been avoided, and I have told people that in no uncertain terms, the air was blue."