Nottingham Forest transfer target Chris Burke scored twice against them for Birmingham in an unhappy St Andrew's return for ex-Blues boss Alex McLeish.
Burke curled a glorious left-foot effort off the underside of the bar from the edge of the area on half-time.
He added another on 79 minutes after substitute Nathan Redmond beat two men to set up a simple tap-in.
Forest's Billy Sharp scored a consolation penalty in stoppage time after Curtis Davies had tripped him.
The visitors had started the game brightly, Chris Cohen playing a one-two with Sharp before firing straight at Jack Butland, now on loan with Blues after being sold to Stoke on transfer deadline day.
At the other end, Karl Darlow had to push away a loose ball at his near post after Davies's header had caused panic in the Forest defence.
Sharp sent a header just past the far post for the visitors from an Andy Reid cross, while Butland reacted quickly to punch clear Greg Halford's header.
But it was home winger Burke, whom Forest had sought to sign in the January transfer window, who broke the deadlock, curling the ball in via the crossbar from 18 yards.
Halford squandered another wonderful chance for Forest early in the second half when he nodded over unmarked from seven yards.
And 10 minutes from time, Blues sealed it, Redmond skipping past two defenders before squaring for Burke to tap in his second, before Sharpe added a consolation from the spot.
For the hosts, victory brings the breathing space of a six-point gap to the relegation zone, while defeat at a tempestuous St Andrew's completes an eventful few days for Forest boss McLeish.
On Friday, Forest chairman Fawaz Al Hasawi said his relationship with his manager was cordial despite McLeish reportedly considering his position at the club after Peterborough's George Boyd's move to the City Ground collapsed.
Birmingham manager Lee Clark:
"I just wish we could have got that elusive clean sheet. I was disappointed we didn't win by a bigger margin with the chances we had particularly in the second half.
"I am enjoying it at the moment because we have a lot of pace in the team when we break.
"Chris Burke is back to his form of last season when he was the best player in the Championship.
"In the last seven or eight games he has been fantastic and I am glad we turned down what wasn't the biggest of bids for him from Nottingham Forest."
Nottingham Forest manager Alex McLeish:
"When you lose goals like we did against Birmingham it is pretty tough to watch.
"There is not a lot I can control about that, as the players have to take real responsibility and make sure they do not concede silly goals as they did against Birmingham.
"It was pretty unprofessional to concede a goal with only 45 seconds to go in the first half."
- 01 Butland
- 04 Caldwell
- 06 Davies
- 28 Caddis
- 30 Robinson
- 07 Burke
- 14 Gomis Booked (Reilly - 63' )
- 15 Elliott Booked
- 09 King
- 20 Thomas (Zigic - 71' )
- 29 Hall (Redmond - 52' )
- 13 Doyle
- 27 Hancox
- 08 Mullins
- 22 Redmond
- 33 Reilly
- 11 Lovenkrands
- 19 Zigic
- 12 Darlow
- 03 Harding
- 05 Collins
- 15 Halford
- 36 Jara
- 06 Moussi (Majewski - 55' )
- 08 Cohen (Blackstock - 83' )
- 11 Reid
- 22 Lansbury
- 09 Henderson (Cox - 71' )
- 24 Sharp
- 35 Khaled Al Rashidi
- 32 Ward
- 04 Gillett
- 10 McGugan
- 28 Majewski
- 19 Cox
- 23 Blackstock
Live Text Commentary
Full Time The referee signals the end of the game.90:00 +3:17
Henri Lansbury concedes a free kick for a foul on Nikola Zigic. Nathan Redmond restarts play with the free kick.90:00 +2:44 Goal scored
Goal! - Billy Sharp - Birmingham 2 - 1 Nott'm For Placed penalty scored by Billy Sharp. Birmingham 2-1 Nottm Forest.90:00 +2:10 Booking
Booking Wade Elliott receives a caution for unsporting behaviour.90:00 +1:30
Foul by Curtis Davies on Billy Sharp, Penalty awarded.89:36
The assistant referee flags for offside against Simon Cox. Free kick taken by Jack Butland.86:53
Corner from the right by-line taken by Andy Reid, save made by Jack Butland.86:16
Unfair challenge on Radoslaw Majewski by Wade Elliott results in a free kick. Direct free kick taken by Danny Collins.85:22
The offside flag is raised against Marlon King. Henri Lansbury takes the indirect free kick.84:11
The ball is crossed by Gonzalo Jara Reyes, save made by Jack Butland.83:52
Curtis Davies gives away a free kick for an unfair challenge on Billy Sharp. Free kick taken by Henri Lansbury.82:31
Paul Caddis takes the free kick.82:31 Substitution
Substitution Dexter Blackstock joins the action as a substitute, replacing Chris Cohen.82:31
Christopher Burke fouled by Dan Harding, the ref awards a free kick.81:19
The assistant referee flags for offside against Simon Cox. Steven Caldwell takes the free kick.80:56
Nathan Redmond produces a left-footed shot from just outside the box that misses to the right of the target.80:10
Andy Reid takes the outswinging corner, clearance made by Nikola Zigic.79:07
The assist for the goal came from Nathan Redmond.79:07 Goal scored
Goal! - Christopher Burke - Birmingham 2 - 0 Nott'm For Christopher Burke gets on the score sheet with a goal from close in to the bottom right corner of the goal. Birmingham 2-0 Nottm Forest.78:56
Nathan Redmond produces a cross,
Centre by Andy Reid, Curtis Davies manages to make a clearance.76:53
Centre by Dan Harding, Curtis Davies manages to make a clearance. Outswinging corner taken left-footed by Andy Reid, clearance by Nikola Zigic.76:03
The offside flag is raised against Billy Sharp. Free kick taken by Jack Butland.74:30
Paul Robinson delivers the ball, Henri Lansbury makes a clearance.73:51
The ball is swung over by Andy Reid, Jack Butland makes a save.73:32
The official flags Marlon King offside. Danny Collins restarts play with the free kick.72:15
Andy Reid produces a cross.70:41 Substitution
Substitution Nikola Zigic joins the action as a substitute, replacing Wes Thomas.70:41 Substitution
Substitution Simon Cox is brought on as a substitute for Darius Henderson.69:17
Chris Cohen takes a shot. Jack Butland makes a save. Inswinging corner taken by Andy Reid, Radoslaw Majewski takes a shot. Jack Butland makes a save. Andy Reid takes a short corner.68:52
The assistant referee flags for offside against Marlon King. Indirect free kick taken by Greg Halford.67:17
Wes Thomas has an effort at goal from just inside the box that misses to the right of the goal.66:47
Centre by Andy Reid.66:16
Shot by Christopher Burke from a long way out goes over the crossbar.64:39
The ball is crossed by Dan Harding.63:35
Centre by Andy Reid, clearance made by Paul Robinson.62:29 Substitution
Substitution Morgaro Gomis goes off and Callum Reilly comes on.61:33
Billy Sharp takes a shot. Jack Butland makes a save.60:25
Greg Halford restarts play with the free kick.60:25 Booking
Booking Morgaro Gomis receives a caution for unsporting behaviour.60:10
Morgaro Gomis gives away a free kick for an unfair challenge on Henri Lansbury.59:02
Andy Reid produces a cross, save made by Jack Butland.57:06
Foul by Dan Harding on Paul Caddis, free kick awarded. Jack Butland takes the free kick.56:44
Free kick awarded for an unfair challenge on Radoslaw Majewski by Morgaro Gomis. Direct free kick taken by Gonzalo Jara Reyes.55:21
Free kick awarded for an unfair challenge on Billy Sharp by Wade Elliott. Direct free kick taken by Dan Harding.54:43 Substitution
Substitution Radoslaw Majewski is brought on as a substitute for Guy Moussi.54:11
Darius Henderson takes a shot. Jack Butland makes a save.53:51
Free kick awarded for an unfair challenge on Billy Sharp by Paul Robinson. Free kick taken by Gonzalo Jara Reyes.53:02
The official flags Billy Sharp offside. Indirect free kick taken by Jack Butland.51:42 Substitution
Substitution Nathan Redmond joins the action as a substitute, replacing Robert Hall.51:42
Shot by Marlon King from deep inside the penalty area misses wide to the left of the target.49:57
Outswinging corner taken left-footed by Andy Reid from the left by-line, Greg Halford produces a header from inside the six-yard box that clears the bar.48:45
Centre by Marlon King, clearance by Henri Lansbury.48:28
Christopher Burke crosses the ball, Greg Halford makes a clearance.46:54
Robert Hall fouled by Henri Lansbury, the ref awards a free kick. Robert Hall crosses the ball in from the free kick, clearance by Guy Moussi. The ball is crossed by Christopher Burke, clearance made by Gonzalo Jara Reyes.46:22
Inswinging corner taken by Robert Hall from the right by-line, Darius Henderson manages to make a clearance.45:26
The ball is sent over by Paul Caddis, clearance by Greg Halford.45:01
The referee gets the second half started.45:00 +3:15 Half time
Half Time The ref blows to signal half-time.45:00 +0:32
Marlon King provided the assist for the goal.45:00 +0:32 Goal scored
Goal! - Christopher Burke - Birmingham 1 - 0 Nott'm For Christopher Burke fires in a goal from long range high into the middle of the goal. Birmingham 1-0 Nottm Forest.44:32
Andy Reid takes a shot. Jack Butland makes a save.42:29
Free kick awarded for a foul by Robert Hall on Henri Lansbury. Andy Reid crosses the ball from the free kick left-footed from left channel, free kick awarded for a foul by Chris Cohen on Jack Butland. Jack Butland takes the free kick.41:19
Centre by Paul Robinson, save by Karl Darlow.40:11
The assistant referee signals for offside against Billy Sharp. Jack Butland takes the indirect free kick.38:46
Long range effort from Morgaro Gomis misses to the left of the goal.38:38
The ball is delivered by Christopher Burke, Greg Halford makes a clearance.36:57
The ball is delivered by Marlon King, save made by Karl Darlow.35:57
The ball is crossed by Christopher Burke, Henri Lansbury manages to make a clearance.32:36
Unfair challenge on Guy Moussi by Morgaro Gomis results in a free kick. Direct free kick taken by Guy Moussi.29:36
Corner taken left-footed by Robert Hall to the near post, clearance made by Billy Sharp.28:43
The ball is crossed by Andy Reid, save by Jack Butland.27:30
The ball is sent over by Gonzalo Jara Reyes, clearance made by Steven Caldwell. Inswinging corner taken left-footed by Chris Cohen, Jack Butland makes a save.25:37
The ball is sent over by Andy Reid, Header from close range by Billy Sharp misses to the right of the goal.25:02
The assistant referee signals for offside against Wes Thomas. Karl Darlow restarts play with the free kick.24:43
Morgaro Gomis fouled by Chris Cohen, the ref awards a free kick. Free kick taken by Steven Caldwell.24:14
Christopher Burke produces a cross, clearance by Guy Moussi.23:27
Free kick awarded for an unfair challenge on Morgaro Gomis by Guy Moussi. Free kick taken by Jack Butland.21:35
Effort from deep inside the area by Marlon King misses to the left of the goal.19:50
The ball is crossed by Robert Hall, Gonzalo Jara Reyes manages to make a clearance.18:18
Free kick awarded for a foul by Greg Halford on Wes Thomas. Corner from the left by-line taken by Robert Hall, clearance made by Billy Sharp.17:44
The official flags Darius Henderson offside. Jack Butland restarts play with the free kick.12:08
Effort on goal by Billy Sharp from just inside the penalty area goes over the target.11:47
Christopher Burke produces a cross, Danny Collins makes a clearance.9:43
Andy Reid delivers the ball.6:45
Robert Hall takes the inswinging corner, Steven Caldwell has a headed effort from close range and clears the bar.6:21
Unfair challenge on Wes Thomas by Henri Lansbury results in a free kick. Direct free kick taken by Paul Caddis.4:36
Darius Henderson is caught offside. Jack Butland takes the indirect free kick.4:11
Wade Elliott challenges Andy Reid unfairly and gives away a free kick. Andy Reid restarts play with the free kick.2:43
Centre by Christopher Burke, Karl Darlow makes a save.1:57
Chris Cohen takes a shot. Jack Butland makes a save.0:24
Foul by Darius Henderson on Steven Caldwell, free kick awarded. Jack Butland restarts play with the free kick.0:00
The ref blows the whistle to start the match.
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