Danny Graham prodded in to give Boro the advantage, then Jacob Butterfield slammed a spectacular half-volley past future Teessider Darren Randolph to make it two-nil.

But Emyr Huws hit back for Birmingham with a spectacular long-range effort of his own.

Kenneth Omeruo and Ben Gibson were both booked for bringing an end to a Birmingham counter-attack, a second yellow card for the on-loan Nigerian which saw him dismissed. 

Gibson was also given his marching orders minutes later for a tug on the shirt of Nikola Zigic.

Despite only having nine men on the field, it was Boro who grabbed the game's fourth and final goal, Lee Tomlin capitalising on a defensive mix-up to smash home and put the contest to bed.