Roberto Soldado's embarrassing mistake paved the way for Tottenham's Europa League exit against Fiorentina.
The trip to Florence was always going to be a tough ask for Mauricio Pochettino's side, given the last-32 tie was poised at 1-1 and their Capital One Cup final against Chelsea loomed large.
The Spurs head coach insisted beforehand that Sunday would not be a distraction and that this was merely their ``first final'' -- one in which they paid for a lack of cutting edge, with second-half efforts from Mario Gomez and Mohamed Salah securing Fiorentina a 2-0 victory.
Things could have so different had Christian Eriksen been awarded an early penalty or, more importantly, Soldado not produced another clip for his growing reel of gaffes.
Clearly bereft of confidence, the misfiring striker decided to pass out to Nacer Chadli when through one-on-one, only for the under-hit ball to be easily gathered by Fiorentina goalkeeper Neto.
It was a shocking error that Pochettino's men would pay for on a night in which their bright start at the Stadio Artemio Franchi would peter out.
After handball appeals against Federico Fazio and a wasted chance by Milan Badelj, both were involved as the latter read the former's poor pass and played through Gomez to fire home.
It was not long until Spurs, who saw goalkeeping coach Toni Jimenez sent off, were punished once again as Jan Vertonghen was dispossessed by Salah and the Chelsea loanee lashed home.
Substitute Harry Kane did find the net, only for offside to be called on a night which was is far from ideal preparation for Sunday's trip to Wembley.
It was not the way Tottenham's impressive 2,200 travelling support hoped things would go after a far from welcome reception in Tuscany.
The flare-up before last week's clash between Roma and Feyenoord led to a city-wide alcohol ban and strong police presence.
Town squares and key monuments were protected, but there were no reports of unrest ahead of a match which began at quite the tempo.
Vlad Chiriches' inability to clear effectively resulted in Badelj screwing wide shortly, before Fazio turned behind a Marcos Alonso cross after another mistake by the Romanian.
Spurs soon started to make inroads themselves as Erik Lamela had a snapshot, before former Manchester City defender Stefan Savic appeared to get Eriksen rather than the ball -- yet the additional assistant referee allowed a corner to be given.
Salah and Gomez led counter-attacks in this entertaining, open match, with Benjamin Stambouli seeing an effort blocked before the blundering Soldado wasted a glorious opportunity.
Lamela played an exquisite, side-splitting ball to put the Spaniard in, yet he chose to roll the ball to the overlapping Chadli rather than strike -- an awful pass so weak that Neto was able to collect.
Fiorentina fans could not believe their luck, jumping to their feet like they had scored -- emotion which quickly turned to anger as handball appeals against Fazio were waved away.
Salah volleyed well over before half-time was called, with the second period just six minutes old when the hosts wasted a fine chance. Ben Davies sliced a clearance into the path of Badelj -- but his fierce effort was straight at Hugo Lloris.
It was not long until the Croatia international was helping Fiorentina to score, though. A poor Fazio pass was picked off by the midfielder, who put Gomez through and the striker impressively struck a low, left-footed effort past Lloris.
Jimenez missed the goal after being sent to the stands for expressing his anger at officials.
Spurs were now clinging onto the tie and had Lloris to thank for keeping it alive, saving from Salah after Joaquin all too easily robbed Lamela.
Kane and Andros Townsend were introduced to give Spurs added impetus, but their need to net was leaving gaps at the back.
Badelj tried and failed to capitalise, but Vincenzo Montella's men soon had a second as dawdling Vertonghen slipped in the box and Salah rifled home.
The 71st minute strike sent Spurs facing an early exit, with Kane's attempt to reduce the deficit ruled out for offside.
Eriksen forced Neto into a save low to his left as the visitors continued to push, with Soldado flicking a header just wide before time was called on Spurs' European campaign.