A superb double from Bryan Mbeumo helped Brentford come from behind to win and spoil Tottenham's final home game of a miserable season.
Mbeumo struck two fine efforts into the far corner early in the second half, before team-mate Yoane Wissa capped things off, as Brentford overturned Tottenham's first-half lead which had come via captain Harry Kane.
Just days after strike partner Ivan Toney was banned for eight months for breaking Football Association betting rules, Mbeumo showed Brentford fans they can count on him to deliver the goals.
It had been a moment of magic from Kane, whose future at Spurs remains in question, when he curled the ball beautifully into the top corner from a free-kick.
It galvanised his team-mates and they played with confidence and flair, creating numerous chances which they should have put away.
Their lack of ruthlessness was punished though as Brentford responded immediately in the second half - Mbeumo taking his chances, firing past goalkeeper Fraser Forster twice in 12 minutes.
Any chance of a late equaliser by Tottenham evaporated when substitute Shandon Baptise robbed Oliver Skipp of possession and Mbeumo teed up Wissa for a comfortable finish.
It was another performance which summed up Tottenham's season - moments of promise before a crushing result.
"The intensity dropped quite a lot in the second half," said interim boss Ryan Mason. "We needed to take our opportunities when they came in the first half.
"They really took theirs. It's difficult to take. It's not just one half of football, you have to do it for the full game."
Tottenham's extremely slim hope of European qualification is fading rapidly, while Brentford know they will finish a successful season inside the Premier League's top 10.
"In many ways it is unbelievable what we have achieved so far this season. Hopefully there is a bit more," Brentford manager Thomas Frank told BBC Sport.
"Maybe, maybe we can push it on the last day and go into Europe. But just a top 10 finish secured, maybe eighth or ninth, we don't know but that is unbelievable."
Same questions for Spurs as Mbeumo shines
A new Harry Kane mural has been painted across the road from the stadium to mark his status as the club's all-time top goalscorerWith very little to play for, most of the focus pre-match was on Kane and his Tottenham future as fans visited the newly-painted mural of their record goalscorer across the road from the stadium.
It was his 300th start in the Premier League for Tottenham but how many more will be added to that tally remains unknown.
He was a bright spark in the early stages alongside Son Heung-min, who himself had several chances to score in the first half.
Brentford's Rico Henry made a crucial goalline clearance to deny Emerson Royal and Arnaut Danjuma flicked a diving header inches wide from Son's cross.
Bar a few half-chances and a dangerous cut-back from Kevin Schade, Brentford did little to trouble goalkeeper Forster until the second half.
But they started on the front foot after the break, getting in behind Spurs' defence and feeding Mbeumo, who took both of his goals extremely well.
From then on, the atmosphere inside the stadium changed as the familiar feeling of defeat crept in and Brentford's support sang teasing chants to increase the pain.
Just as Tottenham began to test Brentford's defence again, Skipp unforgivably lost the ball on the edge of his own box and Tottenham were punished, Wissa coolly stroking it past Forster.
A late header from substitute Richarlison in stoppage time was superbly tipped over the bar by David Raya but some Tottenham fans had already started exiting the stadium - many of them not stopping for a pre-planned lap of appreciation to mark the final home game of the season.
Line-ups
Tottenham
Formation 4-4-2
20Forster
12Emerson Royal6D Sánchez34Lenglet33Davies
16Danjuma38Bissouma4Skipp7Son Heung-min
21Kulusevski10Kane
20Forster12Emerson RoyalSubstituted forPorroat 75'minutes6D Sánchez34Lenglet33DaviesSubstituted forPerisicat 85'minutes16DanjumaSubstituted forLucas Mouraat 66'minutes38BissoumaBooked at 45mins4Skipp7Son Heung-min21KulusevskiSubstituted forRicharlisonat 75'minutes10KaneSubstitutes
9Richarlison14Perisic15Dier23Porro25Tanganga27Lucas Moura29Sarr40Austin51CraigBrentford
Formation 4-3-3
1Raya
2Hickey5Pinnock16Mee3Henry
15Onyeka27Janelt8Jensen
19Mbeumo11Wissa9Schade
1Raya2HickeySubstituted forRoerslevat 89'minutes5Pinnock16Mee3HenryBooked at 68mins15OnyekaSubstituted forDamsgaardat 45'minutes27Janelt8JensenSubstituted forBaptisteat 72'minutes19Mbeumo11WissaSubstituted forDasilvaat 89'minutes9SchadeSubstituted forM Jorgensenat 78'minutesSubstitutes
10Dasilva13M Jorgensen14Ghoddos20Ajer22Strakosha24Damsgaard26Baptiste30Roerslev35TrevittReferee:Jarred GillettAttendance:61,514Live Text
Match ends, Tottenham Hotspur 1, Brentford 3.
Second Half ends, Tottenham Hotspur 1, Brentford 3.
Attempt missed. Pedro Porro (Tottenham Hotspur) right footed shot from outside the box is high and wide to the left.
Attempt blocked. Clément Lenglet (Tottenham Hotspur) header from the centre of the box is blocked. Assisted by Pedro Porro with a cross.
Attempt blocked. Pedro Porro (Tottenham Hotspur) left footed shot from outside the box is blocked.
Corner, Tottenham Hotspur. Conceded by Ben Mee.
Attempt blocked. Pedro Porro (Tottenham Hotspur) right footed shot from the right side of the box is blocked.
Attempt missed. Lucas Moura (Tottenham Hotspur) right footed shot from the centre of the box misses to the right following a corner.
Attempt blocked. Son Heung-Min (Tottenham Hotspur) left footed shot from the centre of the box is blocked.
Corner, Tottenham Hotspur. Conceded by David Raya.
Attempt saved. Richarlison (Tottenham Hotspur) header from the left side of the six yard box is saved in the top centre of the goal.
Attempt saved. Richarlison (Tottenham Hotspur) header from the centre of the box is saved in the bottom left corner. Assisted by Son Heung-Min with a cross.
Corner, Tottenham Hotspur. Conceded by Ethan Pinnock.
Substitution, Brentford. Josh Dasilva replaces Yoane Wissa.
Substitution, Brentford. Mads Roerslev replaces Aaron Hickey.
Goal! Tottenham Hotspur 1, Brentford 3. Yoane Wissa (Brentford) left footed shot from the centre of the box to the bottom left corner. Assisted by Bryan Mbeumo with a through ball.
Delay over. They are ready to continue.
Delay in match (Tottenham Hotspur).
Attempt blocked. Lucas Moura (Tottenham Hotspur) header from the centre of the box is blocked. Assisted by Pedro Porro with a cross.
Substitution, Tottenham Hotspur. Ivan Perisic replaces Ben Davies.
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