Things continue to go from bad to worse for Chelsea, as the Blues suffered their fifth straight loss under Frank Lampard.
Brentford took all three points Bryan Mbeumo sealed the victory off the bench, after Cesar Azpilicueta had earlier put the ball in the back of his own net.
The result leaves Chelsea 11th in the standings - six points off the top-half, while the Bees kept themselves in the fight for European qualification.
More to follow...
Brentford piled more misery on Chelsea with a 2-0 victory after an own-goal by Cesar Azpilicueta and a Bryan Mbeumo strike
Chelsea keeper Kepa Arrizabalaga watches on Cesar Azpilicueta puts the ball in his own net via a Mathias Jorgensen header
It was a frustrating way for Chelsea to go behind as things continue to go against the Blues in what has been a tricky season
Chelsea defender Thiago Silva and his midfield team mate Enzo Fernandez vie for the same ball following a corner kick
Chelsea had a golden chance to bag an equaliser after Pierre-Emerick Aubameyang beat David Raya to a corner
The Chelsea star though could only watch on as the ball went agonisingly over the crossbar to squander a golden chance
Bryan Mbeumo sealed the three points as he cut in off the right flank and expertly placed the ball into the back of the net
Brentford players celebrate with Mbeumo in an important victory which keeps them in the race for European qualification
Frank Lampard has now suffered five straight defeats since he returned to Stamford Bridge as Chelsea's interim manager
David Raya made a number of saves to stop Chelsea including tipping an Enzo Fernandez shot over the crossbar
Chelsea dominated the match in terms of possession and chances created but it was another frustrating match for the Blues
MATCH FACTS
Chelsea: Arrizabalaga, Wesley Fofana, Thiago Silva, Chalobah, Azpilicueta (Aubameyang 46), Fernandez (Joao Felix 79), Kovacic, Chilwell, Kante, Gallagher (Mudryk 46), Sterling (Madueke 79)
Unused subs: Badiashile, Pulisic, Loftus-Cheek, Mendy, Ziyech
Booked: Fofana
Brentford: Raya, Roerslev, Jorgensen, Pinnock, Mee, Henry (Hickey 90+1), Jensen (Baptiste 62), Onyeka (Damsgaard 62), Janelt, Toney (Schade 83), Wissa (Mbuemo 62)
Subs: Dasilva, Ghoddos, Stevens, Cox
Goal Azpilicueta OG 37, Mbeumo 78
Booked: Jensen, Henry
Referee: Andrew Madley