Newcastle - Newcastle edged 10-man Birmingham closer to the relegation zone with a 2-1 victory over the League Cup winners on Saturday.
Birmingham's troubles started in the 35th minute when Liam Ridgewell used his arm to clear the ball in a goalmouth melee, earning himself a red card and conceding a penalty that was converted by Shola Ameobi.
Steven Taylor then made it 2-0 seven minutes later, heading home from a corner curled over by Joey Barton.
Lee Bowyer pulled a goal back on the stroke of half-time with a deflected shot, but Birmingham failed to find an equaliser after the break.
However, the margin of victory would have been far greater had it not been for City keeper Ben Foster, who made stunning saves from Peter Lovenkrands, Nile Ranger and Kevin Nolan twice to keep his side in it to the whistle.
Victory took mid-table Newcastle to 44 points and left Birmingham on 39 - just 16th in the table.
The game kicked off with both sides knowing a win would effectively end their relegation fears, and equally aware that a draw would not be the worst result. And for much of the opening 45 minutes, the game reflected that.
There was little action of note as defences dominated with Ameobi and Lovenkrands seeing little of the ball at one end and lone striker Cameron Jerome, his physical battle with Taylor aside, finding himself equally underemployed.
But the end-of-season feel evaporated in an explosive final 10 minutes of the half.
Newcastle launched a sustained assault with Stephen Carr clearing Ameobi's header off the line and Foster pulling off a fine save to keep out Fabricio Coloccini's follow-up. The Argentine reacted first to head over Foster, only for Carr to intervene once again.
However, as the ball fell toward Nolan, Ridgewell nudged it clear with his arm and referee Chris Foy pointed straight to the spot before producing a red card.
Ameobi waited patiently while Ridgewell made his feelings clear, and then calmly tucked the penalty into the bottom corner for his ninth goal of the season.
Foster made fine reaction saves to deny first Lovenkrands and then Nolan, but there was nothing he could do to keep out Taylor's towering 43rd-minute header, which Sebastian Larsson could only help into his own net.
But Newcastle contrived to hand the visitors a lifeline on the stroke of halftime when Coloccini misjudged a long clearance to allow Cameron Jerome in.
The Argentine and Taylor got back well to halt the striker's progress, but when he fed the ball to Bowyer, his shot ended up in the back of the net via a deflection off Coloccini.
Fullback Jose Enrique fizzed a 35-metre drive just wide of Foster's right post within two minutes of the restart as the Magpies attempted to kill off the game, and Ameobi headed over seven minutes later when he might have done better.
Further chances fell to the home side, but Newcastle had already done enough to secure the points.