Match ends, Blackburn Rovers 2, Birmingham City 0.
Two goals in three first-half minutes helped Blackburn ease to victory and dented Birmingham's play-off hopes.
Tony Watt scored his first league goal for Rovers with a smart turn and finish from Shane Duffy's header.
The hosts doubled their lead when Danny Graham slotted in from keeper Jason Steele's ball forward after City's Clayton Donaldson was denied a penalty.
Birmingham improved in the second half, but Jonathan Grounds' drive against the woodwork was as close as they came.
The win was Blackburn's fourth consecutive home league win - the first time they have managed that for six years.
Defeat means Birmingham, who have slipped further away from the top six, have now won just once in the last 10 on the road, and have a solitary away victory in 2016.
Blackburn manager Paul Lambert: "Watt's goal was a brilliant bit of skill. He's a strong lad, I think he's just got to get fitter, for himself as well.
"He does things that are unexpected and gets people off their backsides and his goal was very good.
"I think Danny Graham has been fantastic, him and Jordi (Gomez). The biggest compliment I can give those two, coming from a Premier League club, is they've fitted in brilliantly, and are playing ever so well."
Birmingham manager Gary Rowett: "The most decisive 10 seconds of the match, if not the season in some ways.
"I'm going to have to temper my words very carefully, just because we're managers and we live and die by the officials' decisions sometimes.
"I just asked the referee the question: why on earth would he go down? He's about to score. There's no benefit to him going down whatsoever, and I think the referee felt as though he went down easily."
- 29EvansBooked at 60mins
- 26LenihanBooked at 73mins
- 14Gomez Garcia-PencheBooked at 45minsSubstituted forGrimesat 50'minutes
- 31BennettBooked at 45mins
- 12GrahamSubstituted forBrownat 86'minutes
- 8WattSubstituted forJacksonat 64'minutes
- 3GroundsBooked at 45mins
- 6KieftenbeldSubstituted forFabbriniat 45'minutes
- 11CotterillSubstituted forBuckleyat 64'minutes
- 19MaghomaSubstituted forSolomon-Otaborat 79'minutes
- Stuart Attwell
- Shots on Target
Second Half ends, Blackburn Rovers 2, Birmingham City 0.
Attempt saved. Viv Solomon-Otabor (Birmingham City) header from the centre of the box is saved in the centre of the goal. Assisted by William Buckley with a cross.
Diego Fabbrini (Birmingham City) wins a free kick in the attacking half.
Foul by Matt Grimes (Blackburn Rovers).
Elliott Bennett (Blackburn Rovers) wins a free kick on the right wing.
Foul by Jonathan Grounds (Birmingham City).
Chris Brown (Blackburn Rovers) wins a free kick in the defensive half.
Foul by Paul Robinson (Birmingham City).
Substitution, Blackburn Rovers. Chris Brown replaces Danny Graham.
Foul by Ben Marshall (Blackburn Rovers).
Jonathan Grounds (Birmingham City) wins a free kick in the defensive half.
Attempt saved. Darragh Lenihan (Blackburn Rovers) right footed shot from the centre of the box is saved in the centre of the goal. Assisted by Elliott Bennett with a cross.
Corner, Blackburn Rovers. Conceded by Diego Fabbrini.
Substitution, Birmingham City. Viv Solomon-Otabor replaces Jacques Maghoma.
Simeon Jackson (Blackburn Rovers) wins a free kick in the defensive half.
Foul by Jacques Maghoma (Birmingham City).
Foul by Danny Graham (Blackburn Rovers).
Paul Robinson (Birmingham City) wins a free kick in the defensive half.
Attempt missed. Elliott Bennett (Blackburn Rovers) right footed shot from outside the box misses to the left. Assisted by Grant Hanley.