But it was Patrick Vieira's men who opened the scoring at Selhurst, after Odsonne Edouard found the back of the net as early as 7 minutes into the game.
The Blues looked second best in the initial stages of the half as Thiago Silva was lucky not to be sent off in the 33rd minute after committing a foul.
Referee Chris Kavanagh was forced to review the incident with VAR but Silva's booking was confirmed to be just a yellow instead of a sending-off.
However, Chelsea roared back into the game after Thiago Silva's header found Pierre Emerick-Aubameyang who smashed home from close range in the 38th minute.
Aubameyang's goal proved to be the last real action in the first half as both sides went into the break with the scores level.
In what was an intense contest between both sides, Chelsea boasted the greater possession.
It looked like the Blues were going to drop points on the road as well up until extra time, when substitute Conor Gallagher scored an absolutely brilliant strike from outside the box to seal the comeback for Chelsea and Graham Potter his first win as Blues coach.
Social Media Reactions
Following the hard-fought victory on Saturday, here's how fans have reacted on social media: