CHARLIE Austin’s 44th-minute strike wasn’t enough for Rangers, who conceded two late goals to spell a first defeat in six Championship matches.
In a largely-untidy encounter at St. Andrew’s, Austin headed home Todd Kane’s cross shortly before half-time to give QPR the lead.
However, just as it looked like the Super Hoops were heading for a seventh win in nine league outings, Aitor Karanka’s Birmingham City turned the tide on minutes 82 and 85.
Kristian Pedersen’s header got the ball rolling for Blues, who stole all three points thanks to Alen Halilovic’s fine effort for the hosts.
Looking to further extend Rangers’ mightily impressive form since the turn of the year, R’s boss Mark Warburton made three changes to his starting XI following Wednesday’s goalless draw at Preston North End.
Lee Wallace missed out with a knock, while Lyndon Dykes and Ilias Chair dropped down to the substitutes’ bench.
Into the team came Chris Willock, Macauley Bonne and Niko Hamalainen.
Rangers lined up as: Seny Dieng, Kane, Rob Dickie, Geoff Cameron, Yoann Barbet, Hamalainen; Dom Ball, Willock, Stefan Johansen; Austin, Bonne.
This contest was relatively scrappy early on, with Birmingham probably edging proceedings.
R’s goalkeeper Dieng pulled off a flying save to deny Gary Gardner on the quarter hour, after the latter let fly from 18 yards.
The first half was far from a thriller in which QPR weren’t exactly at their flowing best. On the half-hour mark, Scott Hogan should have done better with his headed effort after the hosts swung in a ball from the right.
Then, seven minutes later, Dieng tipped Jeremie Bela’s near-post attempt around the post.
None of that mattered come the 44th minute, though, as Rangers edged in front on the stroke of half-time.
The goal owed much to full-back Kane, whose deadly right-flank cross left Austin with the simplest of finishes at the back post.
QPR led at the break – and should have extended their advantage four minutes into the second half.
Willock’s threaded pass put Johansen in behind, but the Fulham loanee could only lash over from 10 yards.
Warburton opted to introduce fresh legs in the 55th minute, as Dykes and Sam Field replaced Austin and Willock.
Dykes made his presence felt soon after coming on – nodding the ball down for Johansen who again shot off-target from 20 yards.
Goal aside, Rangers had already presented more of an attacking threat than they had in the opening period. In the 65th minute, Bonne’s effort on the angle flew just past the upright.
Warburton’s men just needed a second goal to make things that bit more comfortable. On 77 minutes, sub Dykes headed Kane’s lofted centre right at Neil Etheridge.
Two minutes later, Dykes’ box blast forced an important intervention from Marc Roberts.
Unfortunately, an R’s second wasn’t forthcoming and the visitors paid the ultimate price in the final 10 minutes.
First, Pedersen’s headed home a hanging left-wing centre to restore parity.
And Birmingham grabbed all three points three minutes later, as sub Halilovic’s curling effort nestled into the bottom left-hand corner.