Birmingham climbed to fourth after this hard-earned win and are proving one of the hardest teams to beat in the Premiership.

Many of the reasons for that were there for all to see on Saturday. Pompey's slick passing and apparently superior skills counted for little against the home team's rugged defence, powerhouse midfield play and hard running up front.

But in the event it was two sloppy pieces of Pompey defending, one in each half which gifted goals to Stephen Clemence and Stan Laziridis, that decided this lively encounter, and left Pompey manager Harry Redknapp fuming.

Pompey had been the better side early on with Matthew Taylor, in his first league start for six months after his heel injury, and Chelsea loanee Alexei Smertin showing up well in midfield in their first Premiership starts.

But Birmingham snatched the lead with a soft goal in their first real attack on 21 minutes.

A Lazaridis free-kick 25 yards out on the far touchline was curled in towards the far post where former Spurs man Clemence was left unmarked to bundle the ball home from close in.

At the break the nearly 3,000 Pompey fans could look back on several near misses in that half, with Steve Stone's header forcing the former Saints keeper Maik Taylor into a desperate save, Taylor volleying narrowly wide, and Yakubu netting but being harshly ruled offside.

But any hopes of a comeback were dashed five minutes into the second half when Pompey were caught out by a quick Birmingham breakaway, with the otherwise quiet Christophe Dugarry playing a long ball out of defence.

It caught Arjan De Zeeuw and Dejan Stefanovic in the centre of Pompey's defence dreadfully square. Darting between two defenders, Laziridis latched on to the pass and ran on unchallenged to easily slot the ball past the otherwise unemployed Shaka Hislop.

Still, as in the first half, Pompey had the territorial advantage with by far the greater share of the possession but now their work had a distinct air of desperation about it.

Jason Roberts came on in place of the tiring Taylor to team up with Sheringham and Yakubu up front but the formidable defensive pairing of Kenny Cunningham and Matthew Upson were growing in confidence and easily stemming the Pompey tide.

Pompey might have run Birmingham closer if a superb 25-yard effort from Sheringham, on 70 minutes, had gone in rather than crashing against the inside of a post.

Earlier, Russian captain Smertin had forced the Birmingham keeper to dive to his right to claw out a fierce drive, but that was all Pompey had to show for their non-stop pressure.

With their previous home defeat against Blackburn also, this first reverse of the season on the road meant that Pompey had lost consecutive league matches for the first time for 53 games.

They will be encouraged by their performance generally, but both the failure to turn their dominance into goals, and the two pieces of careless defending, cost them dear against a Birmingham side brimful of confidence after their fantastic start to the season.

Most Premiership sides will not relish going to St Andrews at present with the Midlanders in this mood.