Chelsea maintained their perfect start to the season with a hard fought 1-0 at St Andrews over Birmingham City.

Birmingham dominated possession and play for large parts of the game, but they could not find a way through Chelsea's brilliantly organised defensive unit.

The sucker-punch, which always looked likely to come, came just over 20 minutes from time when substitute Joe Cole produced a moment of magic when he skipped his way into the area and fired home.

Cole's goal was harsh on Birmingham who had looked the better team from the beginning.

The first opening of the game came after just three minutes for Julian Gray - playing in an unusual forward role with Mikael Forssell forced to sit out against his parent club - but he could only lash the ball wide after he picked up the ball following Muzzy Izzet's drive.

The deadlock should have been broken ten minutes later when Didier Drogba missed a golden opportunity to open his account in English football when he latched on to Mario Melchiot's mis-timed clearance but from the edge of the six-yard box he placed the ball just wide of Maik Taylor's right-hand post.

Birmingham then took control of the game and there was another defensive error as Emile Heskey latched on to Wayne Bridge's attempted back pass but the England man could not beat Petr Cech in the away goal as he saved with the inside of his leg and the ball bounced away to safety.

Cech then tipped over a Robbie Savage free kick and Heskey headed wide as Steve Bruce's men continued to look the better side.

Ricardo Carvalho, making his first start for Chelsea, was then forced into a dramatic clearance as Stan Lazaridis threatened from the left.

On the stroke of half time, Birmingham could and should have taken a lead into the dressing room.

Damian Johnson saw his 25-yard effort blocked by John Terry and the ball then fell for Gray just five yards from goal but his right footed attempt came back off the inside of the post with Cech beaten and he could only fire the rebound high over the bar.

Coach Jose Mourinho had seen enough and made two changes at the interval with Mateja Kezman and Tiago coming on for the Eidur Gudjohnsen and Alexei Smertin.

However, it was again the home side who looked the most likely and Izzet almost embarrassed Chelsea with an overhead kick but the Turk did not quite connect with his effort.

Former Chelsea duo Jesper Gronkjaer and Melchiot almost combined to put their new side ahead, but the latter headed over after a good cross from the Dane.

As the game went on Chelsea knew they would catch Birmingham on the break as the home side looked desperately for the opener and just before the hour Taylor kept his team level with a wonderful save from Geremi who lashed the ball towards goal from the edge of the area.

Mourinho was criticised following Chelsea's opening day win over Manchester United for being negative, but he kept up the same style as the visitors' first priority looked to be a clean sheet as opposed to breaking the deadlock at the other end.

Birmingham were having little trouble in getting crosses in from wide angles with Gronkjaer and Heskey both playing in dangerous balls - but Chelsea's backline never looked like being beaten.

Chelsea then introduced Cole into the proceedings and within six minutes he broke Birmingham hearts with a strike.

The England midfielder picked up the ball on the left flank and ran at former team-mate Melchiot who showed him the inside. Cole took the route gladly and broke into the area before firing low past Taylor - via the inside of Martin Taylor's leg.

Birmingham were shell-shocked and they could have gone further behind with ten minutes left when Drogba pushed forward and forced Taylor into a hurried clearance, it struck his namesake and fell for the Ivory Coast star but he could only blast over from what was an acute angle.

Heskey then had a half chance when he again won the ball in the area, but under pressure he fired wide and Savage fired over - as Chelsea continued to defend stoutly.

Despite their plethora of new faces, Chelsea showed how far organisation can get you - this display epitomised their coach - whose tactics look ideally suited to the English game.

Birmingham threw everything at Chelsea for the final few minutes, but it was not enough as they lost their opening home game of the new Premiership season.