Garry O'Connor towered to a corner-kick in the 48th minute and steered a weak attempt towards the goal.

But as everyone at the Emirates Stadium waited for an easy save, the ball floated past the Spaniard goalie to level the score line.

Emmanuel Adebayor had put Arsenal in front in the first period, when he successfully converted a penalty-kick home.

The home side dominated the game after the equalizer but failed to penetrate Birmingham's watertight defense.

Arsenal still in charge of the table with 51 points, three ahead of chasers Manchester United, who play Newcastle United later on Saturday.

Birmingham are 16th on 20 points.