"Steven Naismith scored a hat-trick as Chelsea's struggles continued with a third loss in their opening five league games following a defeat at Everton. Naismith came on for the injured Muhamed Besic early on and headed in Brendan Galloway's cross before rifling in a shot to put the Toffees 2-0 up."
Chelsea responded when Nemanja Matic scored with a superb 30-yard effort.
However, the visitors struggled for chances and Naismith slotted in a late angled strike to complete his treble.
Chelsea's tally of four points from a possible 15 means they have made their worst start to a top-flight season since 1986.
The Blues lost only three games on the way to the Premier League title last season.