Substitute Lyndon Dykes scored the winner eight minutes into second-half stoppage time as Birmingham completed a remarkable turnaround to defeat Blackburn 2-1.
It looked like being a harsh reintroduction into the Sky Bet Championship as Blues, after controlling the first half, found themselves a goal down early in the second when Todd Cantwell stroked home a sumptuous volley.
Despite being outplayed in the second half, Birmingham snatched their first league win of the season in dramatic fashion as Jay Stansfield restored parity in the 90th minute with a clinical penalty and Dykes improbably turned the game on its head, sliding in the winner eight minutes later to send 7,000 away fans wild.
It continues their unbeaten start to the season and, for the agony they felt against Ipswich last week, they experienced the ecstasy this week.
The result was cruel on Rovers, who have endured a turbulent week, and could have won it themselves but Makhtar Gueye's late header was repelled before Dykes' telling contribution.
The only chance of note in the first half was Alex Cochrane's low drive that Balazs Toth smartly pushed behind.
Blackburn went ahead in the 50th minute with their first shot of the game and it was well worth the wait. Blues struggled to clear their lines after a Blackburn corner and Christoph Klarer could only head as far as Cantwell towards the edge of the area and he thumped a superb volley into the bottom left corner.
Going behind increased the visitors' urgency, with Stansfield forcing a corner that Ethan Laird headed over from close range before a speculative effort from Tomoki Iwata was easily saved by Toth.
But Blues were increasingly vulnerable and a lightning Rovers break almost yielded a second but Augustus Kargbo's downward header trickled agonisingly wide.
At the other end, Demarai Gray cut inside from the left to give himself a sight of goal but lashed hopelessly wide, much to his visible frustration.
Rovers looked increasingly likely to hang on in the closing stages but with a minute to go, Laird somehow wriggled beyond three Blackburn defenders on the left and was brought down by Sidnei Tavares in the area on the left byline.
Stansfield stepped up and clinically buried his penalty into the left corner for his second of the season.
Rovers cranked up the pressure and a long throw and substitute Gueye saw a powerful header brilliantly tipped away by Ryan Allsop six minutes into stoppage time.
It proved crucial as two minutes later as Gray raided down the right and his right-wing cross was deftly tucked into the left corner by Dykes to end an extraordinary game.
The managers
Blackburn's Valerien Ismael:
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Birmingham's Chris Davies:
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