Christian Eriksen scored his first goal for Brentford as they closed in on Premier League safety by outclassing Chelsea at Stamford Bridge.
Brentford produced a magnificent display to record their first win over Chelsea since 1939 as they came from behind to stun Thomas Tuchel's side with three goals in 10 minutes in the second half before adding a fourth late on to humiliate the Champions League holders.
The Bees enjoyed the better of the first half but were punished for not taking chances when Antonio Rudiger flashed a brilliant 30-yard finish past David Raya three minutes after the restart.
Brentford's response was instant and spectacular as Vitaly Janelt hammered home the equaliser two minutes later before the golden moment in the 54th minute as Bryan Mbeumo squared a pass for Eriksen to score in front of the joyous visiting support.
And Brentford were not finished there, Janelt breaking clear again on the hour to beat Chelsea keeper Edouard Mendy before substitute Yoane Wissa completed their glory day in the closing moments.
Brentford are now on 33 points, 11 clear of Watford, who are third from bottom, and can now surely contemplate Premier League football again next season.
Eriksen stars in fine victory
Christian Eriksen provided the story of this truly remarkable Brentford win with that first goal for the club since making his comeback with the Bees after suffering a cardiac arrest playing for Denmark against Finland at Euro 2020 in June.
It was a wonderful moment but was simply the flourish on a quite brilliant team performance from Brentford, who thoroughly deserved one of the greatest victories in the club's history. The margin of the scoreline did not flatter them.
Thomas Frank's side took the fight to Chelsea from the first whistle, with striker Ivan Toney having three presentable chances as they went right on the front foot.
If there was any disappointment, it was the fact they did not cash in on that superiority, and they paid for it when Rudiger fired Chelsea in front.
Brentford's response was truly outstanding, giving them the result that surely means they will stay in the Premier League next season.
And there is no doubt Eriksen's presence has lifted those around him. Brentford have won all three games he has started since making his comeback as a substitute against Newcastle United in late February.
Eriksen may be the star name but this was the complete all-round display, with Toney giving Chelsea's vulnerable defence a torrid time and Janelt providing the cutting edge.
Brentford were also resolute in defence, with Frank and his players fully deserving the huge ovation they received from their ecstatic fans after the final whistle.
Chelsea get what they deserve
Chelsea can have no complaints about this defeat or the embarrassing scoreline as they were abject in a performance that was completely out of character with their recent efforts.
Tuchel's side won their six matches in March but were never fully switched on from first to last and paid the price.
If there is any consolation for Tuchel - and he will have to search very hard to find any - it is that this did not come in Wednesday's Champions League quarter-final first leg against Real Madrid at Stamford Bridge.
If they repeat this horrible defensive performance, and indeed their entire shambolic effort, their hopes of retaining the trophy they won last June might be over.
Despite the usually reliable presence of Rudiger and Thiago Silva, Chelsea were never unable to control Brentford, who ran them ragged and actually scored have scored more than four goals.
Chelsea must hope this is a blip, rather like their 5-2 home loss to the eventually relegated West Brom last season, because they cannot afford this when Real Madrid come here this week.
The likes of Karim Benzema would have been licking their lips watching this defensive fiasco.
Player of the match
EriksenChristian Eriksen
Chelsea
Squad number7Player nameKanté
Squad number2Player nameRüdiger
Squad number19Player nameMount
Squad number16Player nameMendy
Squad number6Player nameThiago Silva
Squad number29Player nameHavertz
Squad number28Player nameAzpilicueta
Squad number22Player nameZiyech
Squad number11Player nameWerner
Squad number12Player nameLoftus-Cheek
Squad number3Player nameAlonso
Squad number24Player nameJames
Squad number8Player nameKovacic
Squad number9Player nameLukaku
Brentford
Squad number21Player nameEriksen
Squad number11Player nameWissa
Squad number8Player nameJensen
Squad number27Player nameJanelt
Squad number7Player nameCanós
Squad number19Player nameMbeumo
Squad number17Player nameToney
Squad number6Player nameNørgaard
Squad number3Player nameHenry
Squad number1Player nameRaya
Squad number18Player nameJansson
Squad number20Player nameAjer
Squad number30Player nameRoerslev
Squad number5Player namePinnock
Line-ups
Chelsea
Formation 4-3-3
16Mendy
28Azpilicueta6Thiago Silva2Rüdiger3Alonso
19Mount12Loftus-Cheek7Kanté
22Ziyech29Havertz11Werner
16Mendy28Azpilicueta6Thiago Silva2Rüdiger3AlonsoSubstituted forJamesat 55'minutes19Mount12Loftus-Cheek7KantéSubstituted forLukakuat 65'minutes22Ziyech29Havertz11WernerSubstituted forKovacicat 64'minutesSubstitutes
1Arrizabalaga4Christensen5Jorginho8Kovacic9Lukaku17Saúl18Barkley24James31SarrBrentford
Formation 5-3-2
1Raya
30Roerslev20Ajer18Jansson5Pinnock3Henry
21Eriksen6Nørgaard27Janelt
19Mbeumo17Toney
1Raya30Roerslev20Ajer18Jansson5Pinnock3HenrySubstituted forCanósat 88'minutes21Eriksen6Nørgaard27JaneltSubstituted forJensenat 82'minutes19MbeumoSubstituted forWissaat 85'minutes17ToneySubstitutes
7Canós8Jensen11Wissa14Ghoddos22M Jorgensen24Fosu-Henry26Baptiste29Bech Sørensen40FernándezReferee:Andy MadleyAttendance:39,061Live Text
Match ends, Chelsea 1, Brentford 4.
Second Half ends, Chelsea 1, Brentford 4.
Attempt missed. Kristoffer Ajer (Brentford) right footed shot from the left side of the six yard box is just a bit too high. Assisted by Christian Eriksen with a cross following a corner.
Corner, Brentford. Conceded by Reece James.
Attempt missed. Kai Havertz (Chelsea) header from the centre of the box misses to the right. Assisted by Hakim Ziyech with a cross following a corner.
Corner, Chelsea. Conceded by Kristoffer Ajer.
Attempt blocked. Mateo Kovacic (Chelsea) right footed shot from outside the box is blocked.
Reece James (Chelsea) wins a free kick on the right wing.
Foul by Mathias Jensen (Brentford).
Substitution, Brentford. Sergi Canós replaces Rico Henry.
Goal! Chelsea 1, Brentford 4. Yoane Wissa (Brentford) right footed shot from the centre of the box to the bottom left corner following a set piece situation.
Foul by Hakim Ziyech (Chelsea).
Ivan Toney (Brentford) wins a free kick on the right wing.
Substitution, Brentford. Yoane Wissa replaces Bryan Mbeumo.
Corner, Chelsea. Conceded by Christian Nørgaard.
Attempt missed. Antonio Rüdiger (Chelsea) right footed shot from the right side of the box misses to the left. Assisted by Ruben Loftus-Cheek with a headed pass following a corner.
Attempt missed. Antonio Rüdiger (Chelsea) right footed shot from the right side of the box misses to the left following a corner.
Corner, Chelsea. Conceded by Kristoffer Ajer.
Substitution, Brentford. Mathias Jensen replaces Vitaly Janelt.
Attempt missed. Kai Havertz (Chelsea) header from the centre of the box misses to the right. Assisted by Hakim Ziyech with a cross.
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