Blues boss Gary Rowett suffered his first defeat since taking charge of the club as Blackpool ran out 1-0 winners at Bloomfield Road.
A 55th minute strike by Steven Davies was enough to give the hosts all three points as former Blues manager Lee Clark collected his first win as Blackpool boss.
Blues made one change from the side which beat Nottingham Forest last weekend as Lee Novak replaced Andy Shinnie, with the Scot dropping out of the squad altogether with an ankle problem.
In blustery conditions on the seafront, Blues struggled to get into a rhythm for the whole game – a fact which was not helped by a poor playing surface.
David Cotterill had the first chance of the game after eight minutes as he took aim from 30 yards, but his low free kick was palmed away by Tangerines’ ‘keeper Joe Lewis.
With 14 minutes on the clock, Blackpool thought they had taken the lead. Chris Eagles cut in from the left wing to curl a right-footed cross into the area which Davies tapped home, but he was at least two yards offside and was rightly stopped in his celebratory tracks by the officials.
Six minutes later, Stephen Gleeson caught a 25-yard volley sweetly as the ball dropped to him following a headed clearance, but Lewis was again equal to his effort.
Despite not dominating the possession stats, Blues were proving the most likely scorers in a scrappy first-half and after Paul Caddis went in to the referee’s notebook for a foul, Demarai Gray fired an effort at goal from 25 yards, but it was deflected and just skimmed Lewis’ crossbar.
With 12 minutes of the half remaining, Caddis slipped in Novak down the right-hand side, but his drilled cross was hacked off the line by Blackpool’s on-loan defender Kevin Foley.
From the resultant corner, Gleeson found himself on the left in space and when he delivered a deep cross which evaded Lewis, Michael Morrison snuck in at the back post to nod back across goal. However, there was nobody in blue on hand to turn it home to ensure the half ended goalless.
After the break, Blackpool started the second half well and with 10 minutes played, the hosts went in front. A long punt forwards from Lewis was aimed at Davies and he knocked Paul Robinson off balance to slot home past the onrushing Darren Randolph.
It was the only lapse in concentration that Blues suffered at the back for the whole afternoon, but it was to ultimately prove costly for Rowett’s side.
On-loan Norwich winger Jacob Murphy was then denied by Randolph twice in quick succession, firstly after playing a clever one-two on the right wing and secondly from 45 yards after spotting the Irishman off his line.
Morrison was again causing problems from set pieces as he rose highest to meet Cotterill’s corner in the 69th minute but, having got up well, he nodded a tame effort towards Lewis’ goal.
Koby Arthur and Brek Shea replaced Lee Novak and Demarai Gray as Rowett looked to provide further attacking outlets with 20 minutes remaining, but there was no clear chance forthcoming.
With 77 minutes gone, Cotterill whipped a ball in from the left which almost nestled into the far corner after evading all in the box and, two minutes later, Murphy again tested Randolph from range as the hosts looked to counter attack with Blues pushing forward.
Mark Duffy came on to replace Cotterill with six minutes to go but, five minutes later, the substitute fired a free-kick over the bar from 25 yards in what was Blues’ best chance late on.
In the second of five minutes added on at the end of the half, Koby Arthur latched on to a Duffy ball, but he cut inside and scuffed his effort wide as Blues lost for their first time under Rowett.
Blues XI: Randolph; Caddis, Morrison, Robinson, Grounds; Davis, Gleeson; Cotterill (Duffy, 84), Novak (Arthur, 70), Gray (Shea, 70); Donaldson.
Unused subs: Doyle, Eardley, Edgar, Reilly.
Bookings: Caddis (23), Grounds (47)
Blackpool: Lewis; Foley, Nosworthy, Clarke, Kennedy; Eagles (Delfouneso, 58), O’Keefe (McMahon, 61), O’Hara, Perkins, Murphy; Davies (Miller, 65)
Unused subs: Parish, Orlandi, Dunne, Waddington
Goal: Davies (55)
Bookings: Davies (38), Clarke (74), Miller (75), McMahon (89)