Abdoulaye Doucoure's strike and a late effort from youngster Lewis Dobbin handed Everton a 2-0 victory over Chelsea at Goodison Park on Sunday afternoon to move the Toffees four points clear of the relegation zone.
Former Watford midfielder Doucoure followed up on the rebound after Robert Sanchez saved Dominic Calvert-Lewin's effort in the 54th minute, with the visiting Blues unable to muster a response before 20-year-old substitute Dobbin slammed in the hosts' second with his first ever goal for the club.
The defeat is Chelsea's second on the bounce and their seventh in the Premier League already this season and leaves them down in 12th.
How the game unfolded
Everton made just one change from the side that beat Newcastle on Thursday night as James Garner replaced Seamus Coleman. Mauricio Pochettino rang the changes for the visitors, however, with Reece James, Conor Gallagher, Benoit Badiashile and Armando Broja all starting and Raheem Sterling, Lewi Colwill, Thiago Silva and Nicolas Jackson dropping to the bench.
The two sides traded attacks but it was Chelsea who looked more threatening in those opening exchanges. Enzo Fernandez's drive on the edge of the box needed saving from Jordan Pickford before the England international made a sprawling save to stop Cole Palmer's swerving effort from distance from nestling in the top corner.
The Toffees went close when Jack Harrison's acrobatic volley flew past the right post, but the remainder of the first half was filled with possession-based football from Chelsea with little end product and injuries that saw both right-backs substituted.
Reece James, on his fifth consecutive Premier League start, pulled up with a suspected hamstring problem and came off in the 27th minute, while veteran Ashley Young was eventually ran off the ground by speedster Mykhailo Mudryk.
An intricate Chelsea move saw James' replacement Levi Colwill float into the box but the one-time England international couldn't find a finish before Everton threatened at the other end. Dwight McNeil worked some space at the edge of the box and rattled away a shot that Robert Sanchez did well to beat away from goal.
However, the Spaniard was eventually beaten when Doucoure pounced.
An away attack petered out and McNeil raced into free space on the left vacated by Marc Cucurella, charging away from Conor Gallagher to slip in Dominic Calvert-Lewin. His shot was smothered by Sanchez but Doucoure arrived and nailed his shot to put the hosts 1-0 up.
Chelsea's huffing and puffing in the second half failed to produce quality chances. Instead, their patient build-up play was thwarted time and time again by Sean Dyche's Everton, who edged towards the final whistle with their lead still in tact.
Instead of an equaliser, it was the hosts who managed to double their lead and secure all the points. A corner inside the seven minutes of second-half added time fell to youngster Dobbin, who fired in wonderfully to add fresh impetus and belief into Everton's season and consign Chelsea and Pochettino to another disappointing result.
Everton player ratings (4-4-1-1)
GK: Jordan Pickford - 7/10 - A few smart stops in the first half that he would always expect to make and stayed cool under Chelsea pressure late on.
RB: Ashley Young - 4/10 - Couldn't offer much of a defensive response to the sheer pace of Mudryk and made way just before half-time.
CB: James Tarkowski - 7/10 - Composed at the back and arranged his defence perfectly.
CB: Jarrad Branthwaite - 7/10 - Looked to be limping at one stage but recovered and was solid throughout, one ropy challenge that saw him booked aside.
LB: Vitaliy Mykolenko - 8/10 - Defended the space down the left superbly, often forcing Palmer into heavily congested central positions.
RM: Jack Harrison - 6/10 - Another workhorse down the right and had one ambitious strike whistle past the post.
CM: Idrissa Gueye - 5/10 - Booked early on and will miss Everton's next game against Burnley. Largely sat deep as Chelsea played in front of him.
CM: James Garner - 6/10 - Provided a good midfield base first alongside Gueye and then Onana.
LM: Dwight McNeil - 8/10 - Wonderful run down the left exploited the vacant space Chelsea left available before feeding Calvert-Lewin in the lead up to the opener.
AM: Abdoulaye Doucoure - 8/10 - Showed his threat in the final third and stayed composed to belt in the winner.
ST: Dominic Calvert-Lewin - 7/10 - Worked his socks off up front and played his part in the goal, seeing his saved shot fall to Doucoure.
Substitutes
SUB: Nathan Patterson (41' for Young) - 7/10 - Dealt with Mudryk much more comfortably as the Ukrainian had less joy in the second half.
SUB: Amadou Onana (46' for Gueye) - 7/10 - Provided much more coolness in midfield than Gueye, his introduction being crucial as Everton went on to win.
SUB: Beto (67' for Calvert-Lewin) - 6/10 - Had more of a pressing brief up front but did it well and caused some problems with his physicality.
SUB: Lewis Dobbin (86' for Harrison) - 7/10 - The youngster entered the fray late on but had enough time to seal the win with a cracking strike.
Subs not used: Youssef Chermiti, Arnaut Danjuma, MacKenzie Hunt, Ben Godfrey, Joao Virginia
Manager
Sean Dyche - 8/10 - Set his team up in perfect Dyche style, letting Chelsea have a lot of possession while striking when the chances came. Textbook.
Chelsea player ratings (4-2-3-1)
GK: Robert Sanchez - 6/10 - A bit scruffy under a few high balls but positioned himself well to race off his line on occasion and made his first save to deny McNeil. Had to limp off with an injury late on.
RB: Reece James - 6/10 - Performing as expected before suffering a suspected hamstring injury and now faces another nervy wait to discover the prognosis.
CB: Axel Disasi - 5/10 - Sketchy on the ball and statuesque in some situations, especially for Doucoure's goal.
CB: Benoit Badiashile - 6/10 - Showed composure in defence but also had moments where he played Chelsea into trouble from the back.
LB: Marc Cucurella - 6/10 - Caught high up the pitch before Doucoure struck but was at least combative at the back, which can't be said for all of Chelsea's defenders.
CM: Moises Caicedo - 5/10 - Not particularly inventive or useful in possession and wasn't helpful enough in defence.
CM: Enzo Fernandez - 5/10 - Saw as much of the ball as he could have wanted during his 66 minutes but not much inspiration arrived, a few neat dribbles aside.
RW: Cole Palmer - 6/10 - Cut inside and looked to create but often shot from outlandish positions or just couldn't find the right pass.
AM: Conor Gallagher - 6/10 - Only Mykolenko (seven) made more tackles than Gallagher's five, though he couldn't show any goal threat.
LW: Mykhailo Mudryk - 6/10 - Had Ashley Young on toast throughout the first half but his influence lessened as the game progressed.
ST: Armando Broja - 5/10 - A few strong runs here and there to keep possession but didn't do enough with the opportunity.
Substitutes
SUB: Levi Colwill (27' for James) - 5/10 - A nice burst into the box showed quick feet but he oddly chose to stay still and not close down Doucoure before he scored.
SUB: Nicolas Jackson (67' for Broja) - 5/10 - Couldn't offer too much from the bench.
SUB: Raheem Sterling (67' for Fernandez) - 5/10 - Also had a muted appearance as a substitute.
SUB: Djordje Petrovic (84' for Sanchez) - N/A - Came off the bench for his Chelsea debut.
SUB: Ian Maatsen (84 for Cucurella) - N/A
Subs not used: Alex Matos, Leo Castledine, Alfie Gilchrist, Thiago Silva
Manager
Mauricio Pochettino - 4/10 - Couldn't find another plan to break down Everton's defence, his side looking limp in attack for much of the encounter.