Sergio Aguero broke Borussia Monchengladbach's hearts from the penalty spot as Manchester City secured a 2-1 comeback win in Champions League Group D.
Following on from a chastening 4-1 Premier League loss at Tottenham on Saturday, Manuel Pellegrini's team were largely woeful defensively as Monchengladbach thrilled a fervent crowd on their first home match in Europe's top competition for 37 years.
City were indebted to Joe Hart, who brilliantly denied forward Raffael on a number of occasions – most notably from a 19th-minute spot-kick.
A deserved and stylish opening goal arrived nine minutes into the second half from Lars Stindl, heightening the pressure on City who, like the hosts, lost their opening group match.
Nicolas Otamendi endured much of the Bundesliga side's attacking storm but found respite to net a 65th-minute equaliser.
His compatriot Aguero suffered frustrations similar to those of Raffael in front of goal from open play but held his nerve from 12 yards in the 90th minute – sending Yann Sommer the wrong way after being fouled by Fabian Johnson
Probing for early vulnerability in a City defence that proved so porous at White Hart Lane, Johnson drove towards goal and skilfully laid off for Raffael to slice off target.
It was a thrilling, if cavalier, start to the contest and City should have taken fifth-minute lead when Raheem Sterling cut a low ball across from the left and Sommer denied Aguero from point-blank range.
Patrick Herrmann shot wide on a lightning counter-attack and Raffael passed up an even better opportunity to put the hosts in front, blasting his penalty too close to Hart following Otamendi's clumsy foul on the Brazilian forward.
Hart should have had an assist to his name moments later when Aguero latched onto his raking ball downfield but fired wastefully past the post.
The Argentina international manufactured space to shoot left-footed in the 29th minute but the result was the same, with Sommer's far upright untroubled.
A shambolic and overly exposed City defence were indebted to Hart as he superbly frustrating Raffael twice more before the break, while Monchengladbach midfielder Stindl was booked for a dive in the box despite replays suggesting Fernandinho made contact.
Yaya Toure, substituted with a tight hamstring at Tottenham and wholly ineffective here, was replaced by Fernando for the start of the second half as Raffael and Hart resumed their duel.
The outcome was familiar – the England goalkeeper excelling himself after Raffael sprung City's flimsy high line – but Hart was finally beaten in the 54th minute.
City left-back Aleksandar Kolarov allowed Julian Korb ample room on the right to pick out Stindl, who swept home a low finish.
The visiting centre-backs found the ideal way to atone for their ordeal at the other end by combining to equalise 11 minutes later.
Martin Demichelis looked to have turned Kevin De Bruyne's corner over the line and Korb shovelled the ball as far as Otamendi, whose rasping shot deflected into the net off Andreas Christensen.
Pellegrini's side carried by far the greater threat in the closing stages but had to wait until the death to seal all three points, Johnson the villain after a corner from substitute Jesus Navas was sloppily dealt with.
A cool Aguero settled matters to leave City level on points with Sevilla and three behind their matchweek-one conquerors Juventus, with Monchengladbach desperately unlucky to not get off the mark.