Three quickfire goals including Christian Eriksen's first in the Premier League since 2019 helped Brentford stun Chelsea 4-1 for their first victory at Stamford Bridge since 1939.
Chelsea took the lead on 48 minutes with a stunning strike from Antonio Rudiger, who smashed in from 35 yards.
But Brentford replied only 100 seconds later as Vitaly Janelt drilled in a shot from the edge of the area.
The visitors went in front after 54 minutes as Eriksen tucked in Bryan Mbeumo's cross from close range following a counter-attack.
Janelt dinked Ivan Toney's through-ball over Edouard Mendy to score his second on the hour before substitute Yoane Wissa added a fourth with three minutes remaining.
Brentford climb to 14th with 33 points after a third win in four matches.
A first defeat in seven leaves third-placed Chelsea on 59 points.
See: Chelsea report | Brentford report
Next fixtures
Chelsea: 9 Apr v Southampton (A)
Brentford: 10 Apr v West Ham (H)
Match officials
Referee: Andy Madley. Assistants: Dan Cook, Wade Smith. Fourth official: Andy Woolmer. VAR: David Coote. Assistant VAR: Lee Betts.
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