Chelsea suffered only their second home league defeat under Jose Mourinho as they went missing in action against a well drilled Crystal Palace.
They looked to be on the up at the end of a dour first half, but their visitors went ahead through Bakary Sako on 65 minutes.
Radamel Falcao equalised 14 minutes later, with his debut goal for Blues, but the winner came through Joel Ward just 100 seconds later.
Chelsea are enduring their worst start of the Roman Abramovich era, with just four points from four games.
