Clayton Donaldson's strike just after the hour mark earned Birmingham a vital 1-0 Sky Bet Championship win at Rotherham.
Donaldson kept his cool to tuck home a rebound and lift Birmingham above the Millers in the table.
Backed by more than 2,500 fans, Birmingham had the better of the opening exchanges and produced the first effort on goal through Stephen Gleeson's free-kick.
His 25-yard effort did not have enough on it to trouble Rotherham goalkeeper Adam Collin.
At the other end Ben Pringle picked out...