English FA Premiership/ Birmingham City 0 Chelsea 0: The idea of Chelsea blowing the Premiership after leading it since August is bizarre but at least it has become a matter worthy of discussion. In little more than a fortnight the gap at the top of the table has been reduced from 15 points to seven. Something is up with Jose Mourinho's team.

Not that the Chelsea manager will admit to being concerned. "We have three matches at home and three away," he said on Saturday.

"If we win the three matches at home we are champions."

True enough but the last of these is against Manchester United, whose drums are growing ever louder. Should Chelsea's dysfunctional form continue, the Premiership may see a climax rather than a cakewalk.

Nothing is impossible. For example, the notion Birmingham City, who in their previous home match had conceded seven goals to Liverpool in the FA Cup, would 11 days later become the first team this season to hold the champions to a scoreless draw in a league fixture was implausible.

For all the renewed grit and determination Birmingham displayed their finishing remained wayward. Playing with a lone striker who had scored once in 18 matches did not help. At present Emile Heskey could not penetrate a dutch barn let alone hit a barn door.

Chelsea's shooting was scarcely better. They dominated the second half, yet the final snap in front of goal was missing and, when Hernan Crespo did control a ball from Joe Cole with an astute touch before producing a sharp volley, Maik Taylor was in position to block it.

Twice a flag denied Chelsea the lead. Damien Duff was offside after 57 minutes but Mourinho was convinced Asier Del Horno's goal, seven minutes earlier, should have been allowed. As Arjen Robben took a free-kick on the right Ricardo Carvalho ran back from an offside position to challenge for the high ball.

Though he did not make contact he took defenders with him, which was why the linesman ruled him interfering with play, before the ball dropped for Del Horno to head it in. "Carvalho is not offside," Mourinho insisted. "He doesn't interfere with the game." Bruce disagreed.

"If you are in the six-yard box standing in an offside position, then you are offside," he said. Mourinho, despite his disappointment, felt Birmingham deserved their point "for the way they fought".

If anything Bruce's team performed better without the ball than when they had it.

Nicky Butt followed Fulham's example of close-marking Claude Makelele and again this had the effect of a hand-gripping Chelsea's windpipe. Frank Lampard, dogged by Damien Johnson, looked heavy-legged and Didier Drogba was well stalked by Martin Taylor.

Olivier Tebily did more than anyone to carry the play to Chelsea in the first half and his 25-yard shot, which Petr Cech tipped over the bar just before the quarter-hour, turned out to be the sum of Birmingham's serious attempts to score.

Bruce was entitled to be pleased with his team's response to a bad couple of weeks and Birmingham's owner, David Sullivan, may like the players a little more than he did.

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