Four minutes into added time Pepe Reina's second-half resistance was finally ended in a devastating, chaotic finish for Aston Villa.
Reina had performed brilliantly, producing five outstanding saves in the second half, but his one-man barricade collapsed as Son Heung-min secured Tottenham a crucial victory in their pursuit of a Champions League place.
It is now over 12 years since Spurs last suffered defeat at Villa Park and this result will feel like a potentially pivotal moment for Jose Mourinho after an absorbing, crazy encounter.
Son's winner lifted Spurs into fifth place, one point behind Chelsea, and Mourinho is now seven games unbeaten ahead of the trip to Stamford Bridge this weekend.
Mourinho's mission could also be boosted by Manchester City's potential two-year ban from European competition for breaches of Uefa's financial regulations.
If City fail with their appeal, it means fifth place could secure entry into next season's Champions League, and Mourinho was in mischievous mood when asked about the possible ramifications.
"Uefa have to analyse, and if I go into that I have to ask if the team which finished second (his Manchester United side) in 2018 are going to be champions, yes or no?" he said.
"Joking apart, at the end of the season we'll see where we are. If we are sixth or seventh ,it doesn't matter.
"Wolves, Sheffield United, Manchester United, Arsenal, Everton - everyone looks to the table and says 'we can do it'. It's going to be hard.
"It's not about huge decisions or small decisions, it's about the rules, the law, it is or it isn't. Uefa punished them but they have the chance to appeal.
"Until the appeal has finished, Manchester City have the benefit of the doubt."
Mourinho had insisted before this game that Spurs are one one of at least five clubs "smelling the opportunity" to finish in the Champions League spots. They will certainly have the scent in their nostrils after this dramatic afternoon.
Spurs were far from polished, defensively suspect but at times exhilarating going forward, with Son's dramatic goal sparking wild scenes of celebration at the end.
Mourinho said: "A team without (injured striker) Harry Kane is finding difficulties, but in the middle of the difficulties we are finding a different way to play football and create opportunities and to score enough goals to put ourselves in a position to fight for a good position in the table."
Villa did not deserve to lose but these are the fine margins and they are just above the relegation zone. It was a mistake from Bjorn Engels which led to Son's winner. Villa's propensity to concede poor goals is causing them serious problems.
They had started brilliantly and deservedly took the lead in the ninth minute, after a moment Toby Alderweireld and Hugo Lloris will not want to view again.
Anwar El Ghazi's cross from the right took a deflection off Ben Davies and Alderweireld, under pressure from Mbwana Samatta, could only touch the ball over the line. Lloris was also at fault, strangely opting not to come out and clear the cross.
Villa were full of vigour, and Jack Grealish was in the mood. Spurs failed to sign the Villa captain before the start of last season but he has made huge strides since then, taking control of games with a swagger. An England call-up for Grealish next month appears inevitable.
Out of nowhere, Spurs levelled in the 27th minute. They had been struggling for fluency yet Alderweireld atoned for his error by turning quickly in the area to smash the ball into the roof of the net, as Villa failed to clear from a corner.
The momentum of the game swung towards Spurs a minute before half-time. Engels was adjudged to have fouled Steven Bergwijn in the area, following a review.
Son's penalty was saved by Reina but he reacted quickly to stab the loose ball home.
Villa did respond, and levelled in the 54th minute. Grealish swung over a corner and Engels rose above Alderweireld to head the ball past Lloris, his first goal for the club.
Reina had been furious at conceding the goal before half-time and then took centre-stage, producing fine saves from Bergwijn, Son and Dele Alli.
There was still time for the on-loan goalkeeper to save Villa again, diving to his left to prevent Son from finding the corner, but he was beaten at the death.
Engels's error, with the Belgian completely missing an attempted clearance, allowed Son a clear run on goal and he displayed composure to slide the ball under Reina's body.
It was cruel on Villa, who remain one point above the dreaded dotted line. (© Daily Telegraph, London)