The Bees snatched a lead in the 37th minute through a Cesar Azpilicueta own goal before Bryan Mbeumo’s deflected shot beat Kepa Arrizabalaga at the near post in the 78th minute.
The result ensured Chelsea’s miserable season continued, having now lost their last five games in a row in all competitions.
All five defeats have come since Lampard became interim boss, with the Blues scoring just one goal under the Englishman’s stewardship.
Chelsea’s abysmal goalscoring form continued against Brentford, with the team desperately short of cutting edge in attack and painfully fragile in defence despite the host of talents at Lampard’s disposal.
The Blues improved after the break, with Lampard switching things up. They had a few shots on goal but created just one big chance, which they failed to convert.
Despite monopolising possession, Chelsea never really looked like hurting Brentford, but Lampard believes providence is against his side that is bereft of confidence.
“It’s difficult – I feel for the players a bit, obviously at the moment they’re low on confidence,” Lampard told BT Sport after the game.
“In terms of the game, we controlled it all possession-wise. Brentford are good at what they do, so the details of the game are clear. We’re lacking the belief at the top end of the pitch, so you lose a game.
“In this moment, everything is going against us. We have to believe in the games coming up, and they are difficult games.”
Chelsea’s miserable run of form continues, with the Blues now failing to win any of their last eight games, which leaves them languishing in mid-table in the Premier League.
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