Two penalties from Andrew Johnson ensured Crystal Palace secured a crucial victory over Birmingham in their fight against relegation.

Johnson, whose first spot-kick shortly before half-time had to be re-taken, made it 19 goals for the season with this double, which was completed with a second penalty in the 67th minute.

Birmingham defender Matthew Upson was the culprit on both occasions, first fouling Tom Soares before bringing down Johnson himself.

The victory was doubly sweet for Palace fans, who have not forgiven Birmingham manager Steve Bruce for walking out on them to take over at St Andrews in the autumn of 2001.

The home side were fortunate to be ahead at half-time as Bruce's men had created the better chances, but Palace were the only side in contention in the second period and fully deserved to complete a league double over their opponents.

Palace manager Iain Dowie made only one change Birmingham fielded two ex-Palace players in Clinton Morrison and Julian Gray, while Palace duo Andrew Johnson and Michael Hughes have also both played for Blues.

Predictably, Bruce was booed by home fans as he walked to the dug-out accompanied by two security guards.

Neither his current side nor his former team were able to retain possession in the early stages, making for an opening that lacked in shape and quality.

But the match came to life in the 12th minute when Johnson cut into the Birmingham area from the left, but failed to win a penalty as referee Phil Dowd was not conned by his clear dive under the challenge of Tebily.

A minute later, Morrison - whose move to Birmingham from Palace sent Johnson in the opposite direction - missed the first real chance of the game.

Walter Pandiani laid the ball off to Gray - another former Palace man to be greeted with cat-calls from the home supporters - who released Morrison on the right, but the Ireland international shot wide of the left post after forcing his way into the penalty area.

In the 16th minute, Morrison did his former team another favour, inadvertently directing Pandiani's goalbound header wide following a Jermaine Pennant corner.

Birmingham continued to create the better opportunities but, fortunately for relegation-threatened Palace, Bruce's team were in profligate mood.

Palace full-back Danny Granville was able to breathe a sigh of relief in the 28th minute. His failure to judge a bouncing ball allowed Pennant to move into the area from the right, but his cut-back was dreadful and goalkeeper Gabor Kiraly was able to gather with ease.

At the other end, Jamie Clapham made a superb interception to prevent Soares' low ball reaching Andrew Johnson - and in the 41st minute, Palace took a undeserved lead.

Upson was ruled to have impeded Soares as he broke into the area, and Johnson kept his nerve to score from the spot at the second attempt after referee Dowd ruled out his first successful effort, apparently for a team-mate's encroachment.

Perhaps mindful of their good fortune in the first half, Palace were far more purposeful after the break as they searched for the second goal.

In the 52nd minute, Mikele Leigertwood's shot from 25 yards rebounded to Dougie Freedman inside the area, and his mis-hit effort was looping into the net before visiting 'keeper Maik Taylor tipped it over the bar.

Freedman wasted an even better opportunity seven minutes later. Released on the left by the ever-astute Hughes, the Scot eluded Kenny Cunningham but his shot from 10 yards was too weak to trouble Taylor.

Palace continued to dominate, Wayne Routledge firing a 61st-minute free-kick narrowly wide and Johnson shooting straight at Taylor from 10 yards after Cunningham had managed to force him wide.

But England's latest cap did not have long to wait before scoring his second, once more from the penalty spot.

Upson was again the culprit, bringing down Johnson in the 67th minute. And the former Birmingham striker got up to smash home number two against his former club.

Birmingham had sent on Robbie Blake and Darren Anderton for Morrison and Tebily respectively, but the pattern of the match did not change as Palace held onto their advantage comfortably.

Pennant, one of the visitors' livelier players, could have halved the deficit eight minutes from time.

But after evading Granville with a clever piece of control, the pacy winger's finish was disappointing and Kiraly made a simple save.

Gray, who was quiet in the second half, finally got away down the left and crossed for substitute Blake, whose volley-on-the-turn from 15 yards flew wide of Kiraly's right post.

Teams

Crystal Palace: Kiraly, Boyce, Hall, Sorondo, Granville, Routledge (Lakis 90), Leigertwood, Hughes, Soares (Borrowdale 90), Johnson, Freedman (Torghelle 87).

Subs Not Used: Speroni, Kolkka.

Booked: Leigertwood, Hughes, Soares.

Goals: Johnson 41 pen, 68 pen.

Birmingham: Maik Taylor, Tebily (Anderton 73), Cunningham, Upson, Clapham, Pennant, Clemence, Johnson, Gray, Pandiani, Morrison (Blake 63).

Subs Not Used: Vaesen, Diao, Nafti.

Booked: Pennant, Pandiani, Morrison.

Att: 23,376

Ref: P Dowd (Staffordshire).