Following a dramatic FA Cup victory over Leeds United, Chelsea were looking to secure back-to-back wins for the third time this calendar year.
The Blues got off to a strong start, seeing much of the ball in the opening stages at the Gtech Community Stadium.
Nonetheless, it was Brentford’s Yoane Wissa who had the game’s first big chance, striking straight at Dorde Petrovic from close range.
Having won each of their last four London derbies, the Blues were looking to continue that streak here, and they took a big step towards that aim 10 minutes before the break as Nicolas Jackson rose above Zanka, nodding home Malo Gusto’s cross - his first league goal since mid-December.
However, Brentford wasted no time getting a foothold in the contest after the restart, levelling the scores when Mads Roerslev rifled a rebound inside the left post.
Mauricio Pochettino’s side have often been criticised for their ability to withstand pressure, something which their opponents evidently looked to capitalise on as Vitaly Janelt guided a low shot onto the post minutes later.
Momentum eventually swung back towards the visitors, and Chelsea should have taken the lead when Gusto picked out Palmer, who placed a golden opportunity wide of the post.
With the game wide open, Yoane Wissa reacted first to a loose ball, acrobatically volleying beyond Petrovic to put the Bees ahead.
Sergio Reguilon missed the chance to give his side breathing room, striking the foot of the post with a back-post header, allowing the Blues back into the game when Axel Disasi headed in Cole Palmer’s cross following a short corner.
Ultimately, Chelsea’s leaky defence didn't cost them anything more, with the Blues still searching for their first away league clean sheet of the campaign.
As a result, they miss the chance to retake their spot in the top half of the table as their league season threatens to peter out once again.
Meanwhile, despite a hard-earned point, Brentford’s run of two league wins in 13 fixtures (D1, L10) leaves them looking over their shoulder, just six points clear of 18th-placed Luton Town.
Flashscore Man of the Match: Malo Gusto (Chelsea)