Maren Mjelde pounced in the last minute to send Chelsea Women back into the Champions League semi-finals after an extraordinary night at the Stade Jean Bouin in Paris.
Paris St Germain – roared on by around 600 of their Ultras in a crowd approaching five figures – hauled themselves back from a two-goal first leg deficit and even looked set to clinch the tie in normal time.
But just when Chelsea seemed to be content to cling on for an extra 30 minutes, Norwegian international Mjelde drilled a low shot past Christiane Endler to secure a 3-2 aggregate victory and spark jubilation among the small contingent of travelling fans.
Emma Hayes' side had been totally outclassed by their opponents, who grabbed a second-half lead on the night through Kadidiatou Diani before a howler by Chelsea goalkeeper Ann-Katrin Berger pulled them level on aggregate.
Fears of crowd trouble had overshadowed the build-up to the game after a coachload of PSG fans were intercepted before the first leg in London and found to be in possession of weapons and drugs.
PSG are vocally backed at most home games by the Ultras, who have been banned from following the men's team.
The atmosphere generated by their constant, orchestrated singing and drumming is another notable development in a women's game which has seen huge recent crowds in both Italy and Spain.
Hayes, who has spoken passionately about the need to generate atmosphere in the women's game, will have been more concerned about her own side's performance in a first period in which they could only muster a single shot on target.
Two-time finalists PSG went in search of a goal to haul them back into the tie and in truth it was a mixture of resolute defending and sizeable fortune which kept Chelsea's 2-0 lead intact at the break.
Wang Shuang's dangerous free-kick flashed dangerously across the face of goal, Marie-Antoinette Katolo missed with a header and Diani hit a shot into the side netting.
It took 42 minutes for Chelsea to summon their first shot, a tame effort from Ramona Bachmann which was easily held by Endler.
Any hope Hayes had of the interval stalling her opponents' momentum evaporated two minutes into the second half when Diani fired home from a cross by Ashley Lawrence.
The goal was greeted by at least five red flares on the halfway line and the smoke had barely cleared by the time time PSG hauled themselves level on aggregate.
Berger appeared to catch and comfortably hold a 56th minute corner from Wang only to inexplicably drop it over her goalline.
Berger redeemed herself by stopping a shot from Katolo moments later but Chelsea were reeling and Wang almost put PSG ahead with a long-range drive that flashed inches wide.
With extra-time looming, there were signs of Chelsea belatedly stirring. Substitute Fran Kirby sent a low shot just wide, and Sophie Ingle was unfortunate not to connect with Karen Carney's corner in a crowded box.
PSG could have gone ahead on aggregate with five minutes of normal time remaining when Berger again fumbled a Wang corner, but Jessica Carter booted clear off the line and Chelsea were soon celebrating Mjelde's decider.
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