Danny Welbeck netted a stoppage-time equaliser as Brighton hold Chelsea to a 1-1 draw at Stamford Bridge on Wednesday night.
The Blues needed a win to go three points clear of Liverpool in the second position and six behind league leaders, Manchester City who face Brentford on Wednesday.
Thomas Tuchel's men were off to a good start with captain Ceasar Azpilicueta hitting the post with a deflected shot early in the first half.
However, it was Belgium striker, Romelu Lukaku who broke the deadlock two minutes to the half-hour mark.
Chelsea's goal appeared to be a wake-up call for Graham Potter's men who sprung to life afterwards.
Despite going behind by a lone goal, the visitors were undeterred and they dominated the possession, including goal attempts.
The Seagulls came roaring in the second half as Lallana, Mac Allister and Bissouma asked questions of Mendy who pulled some good save to deny the visitors.
Moder was the closest for the visitors having skimmed the crossbar with a chance just after the break.
Brighton's resilience finally paid up before the whistle when Welbeck came off the bench to snatch a late point by heading home the equaliser in a 1-1 draw at Stamford Bridge.
Although Chelsea were deprived of two vital points by the former Manchester United striker, The Blues moved to second place with a point ahead of Liverpool who were defeated by Leicester City on Tuesday night.