Duncan Ferguson made an instant impact as Everton's caretaker manager following the sacking of Marco Silva, guiding them to a 3-1 win over Chelsea and lifting them out of the bottom three.
Silva was sacked on Thursday in the wake of a 5-2 hammering in the Merseyside derby but Ferguson's first game at the helm proved there is life in the Toffees yet, with Chelsea losing for the third time in four Premier League matches.
Richarlison got Ferguson's interim reign off to a flying start when heading in after only five minutes, with the Brazilian netting for the third successive Premier League match.
Dominic Calvert-Lewin capitalised on defensive haplessness to make it 2-0 early in the second half and, although Mateo Kovacic's first league goal for Chelsea offered the visitors encouragement, Everton managed to seal the points late on – their English forward getting a second.
Having found themselves 2-0 down after 17 minutes on Wednesday, the improvement in Everton's start against Chelsea was marked, taking an early lead when Richarlison met Djibril Sidibe's cross with a header the once famously dominant Ferguson would have been proud of.
Calvert-Lewin should have doubled hosts' lead in the 16th minute, but his feeble shot after being released by Theo Walcott was straight at Kepa Arrizabalaga.
Chelsea steadily improved and Tammy Abraham saw a flick from Willian's delivery flash right across the face of goal, but that was as close as they came before half-time.
Everton began the second half with renewed purpose and quickly increased their lead – Calvert-Lewin converting after Kurt Zouma's poor clearance dropped in the box and ricocheted off the Frenchman and Andreas Christensen.
Chelsea swiftly pulled one back through Kovacic, whose controlled volley from 30 yards beat the unsighted Jordan Pickford to find the bottom-left corner.
That paved the way for Chelsea to pile men forward towards the end, but Everton wrapped up the win six minutes from time, Calvert-Lewin prodding through Kepa's legs after the keeper had initially given the ball away under no pressure.
What does it mean? Chelsea looking over their shoulder
Friday's news of Chelsea's transfer ban being halved seemingly could not have been timed any better. If there is one thing made abundantly clear by Saturday's defeat, it is a lack of quality at centre-back.
As a result of Frank Lampard's men being so poor at the back, they could finish the weekend only three points clear of fifth-placed Wolves in they win at Brighton and Hove Albion on Sunday.
Chelsea's centre-back frailties laid bare
All three of Everton goals came as a result of Chelsea's centre-backs failing to do their jobs properly. Neither Christensen nor Kurt Zouma picked up the run of Richarlison for his opener, while the latter's dreadful clearance proved critical for Calvert-Lewin's first strike. His second came after a myriad of blunders, starting with Kepa.
Sidibe shows his class
Both of Everton's full-backs impressed on Saturday, but Sidibe was particularly effective at both ends. On top of his seven tackles, three clearances and four interceptions, the Frenchman also laid on three chances and set up Richarlison's opener.
What's next?
Everton have another tricky contest on the horizon as they go to Manchester United a week on Sunday. Chelsea host Lille in the Champions League on Tuesday, aiming to secure their progression to the knockout phase, before returning to Premier League action at home to Bournemouth next Saturday.
