Aston Villa entered the race for Europe as goals from Ollie Watkins and John McGinn saw them win 2-0 at Chelsea – in a result which saw Graham Potter receive chants of “you don’t know what your doing” from his own team’s fans
Villa went in front when Watkins took advantage of Marc Cucurella's poor defending to lob Kepa Arrizabalaga (18) - but the visitors were indebted to goalkeeper Emiliano Martinez, who pulled off a string of superb saves to keep his side ahead
The Argentine World Cup winner made two smart one-on-one stops to deny Mykhailo Mudryk, as well as Kai Havertz on several occasions
Chelsea saw a Ben Chilwell header ruled out for a push by the full-back on Ashley Young before half-time - and the Blues received a sucker punch after the interval as McGinn's long-range stunner from distance found the bottom corner
The result moves Chelsea down to 11th in the table - 11 points off fourth and nine behind fifth-placed Newcastle having played two games more
After the game, Chelsea boss Potter admitted his side put in a positive performance - apart from when his side came to deal with both penalty areas
"In both boxes we were second best," he told 
 "The first goal was disappointing from our perspective
 We need to do a little better there, of course
"But there were a lot of good things in the game, a lot of attacking play, attacking entries, shots
 if you look at the stats of the game, it's a positive performance
 But because of the scoreline it's not
 We're down in the game and we're really disappointed
"Villa, meanwhile, climb to ninth with defeats for Liverpool and Fulham earlier on Saturday, as well as Brighton and Brentford's draw, meaning Unai Emery's side are now just two points off sixth
An end-to-end encounter began in brilliant fashion as both sides had big chances to take the lead in the opening seven minutes
Mudryk picked Boubacar Kamara's pocket on the edge of the box after an unsympathetic pass by Martinez - but the Villa goalkeeper made amends by staying big and keeping out the Ukrainian's effort
Seconds later, Villa were in on goal as John McGinn slipped in Watkins for a one-on-one - but the striker dragged his effort wide when he had more time
Villa's confidence continued to grow as McGinn struck the bar after being fed by Emiliano Buendia on the edge of the area - but they found the opener a minute after that, and Watkins was not to be denied this time
Douglas Luiz's long pass saw both Kalidou Koulibaly and Cucurella jump for the ball, only for the latter to flick the ball on to the onrushing Watkins, who lobbed Kepa with a simple finish
 That goal made Watkins the first Villa player to score in five consecutive away league matches
Chelsea tried to make amends straight away as Joao Felix's near post effort was kept out by Martinez, while Enzo Fernandez flashed a header wide of the near post
Then came Chelsea and Mudryk's big moment
 The winger was played in and clear through down the left channel but took his shot way too early, with his low effort an easy grab for Martinez
Havertz was then twice denied by flying bodies and Martinez before half-time, before referee Andy Madley ruled out Chilwell's header past the Villa goalkeeper for a push on Young
Chelsea and Chilwell began the second period brightly with the defender flashing two efforts wide - but then came Villa's second just as the Blues were beginning to build momentum
A corner was cleared as far as Jacob Ramsay, who fed Scottish midfielder McGinn whose first-time effort from the edge of the area nestled into Kepa's far corner
Under-fire Potter - who started to draw the ire of a section of the Chelsea home crowd - brought on Noni Madueke and N'Golo Kante and both had quick-fire chances
Madueke curled wide of the far post on the break, while Kante - playing his first game in seven months and 17 days after injury - missed Chelsea's best chance of the second period by flashing wide when unmarked inside the box
Apart from a wild Mateo Kovacic shot from distance, Villa had little Chelsea threat to deal with after that
In fact, Villa were the team closest to a third as Leon Bailey curled wide, before Reece James' backpass was picked up by Watkins, who was denied at his feet by Kepa
 A moment that perfectly depicted Villa's sharpness and Chelsea's clumsiness
Potter doubled down on his comments that Chelsea played well in their defeat, admitting while the scoreline was painful, his team had positive intent
"If you look at the stats, apart from most important stat, there was a lot that said we did well," he said
"It's difficult, when you're 1-0 down at home, but the team gave everything
 The intention of the team was there
 You can tell the amount of times we got in box, we had positive intent
 The scoreline was painful for us
"We came in September, there's a lot of games, a lot of injuries
 It's difficult to have consistency you want as you're playing a lot of matches
 Today is a bit of a setback, of course it is, we're disappointed to lose
 At home, we can feel the pain the of supporters
 We have to dust ourselves down and go again for Tuesday
"I understand when you lose at home, the emotions of the game is such that people are going to be disappointed, frustrated
 angry
 We're not happy with where we are in the table
 Whatever criticism comes, we have to accept
"Potter also defended Mudryk and Cucurella for their errors in the game, saying they are his responsibility
Asked about Cucurella's mistake, Potter said: "It's football, one action
 It can happen
 It's miscommunication, I think
 That's for me to take responsibility for and do better with
"Even though we had opportunities ourselves and attacked well, we gave up too many opportunities
 The one with Watkins is the one that sticks to mind
"Apart from that, there wasn't much [in it]
 At the same time we had two bigger chances [for Mudryk], that's on me
 I have to take responsibility
"Meanwhile, Villa manager Emery hailed goalkeeper Martinez for his string of saves - and says he is "clearly" one of the best three to five 'keepers in the world
"Today is the example
 He is very demanding of himself
 His career progression is going up and is practicing a lot," said the Spaniard
"He's showing ambition
 He's 30 and he deserves all things happening to him
 Now he is clearly the one of the best goalkeepers in world
 Clear
 No 1? I don't know
 If I can speak about five or three goalkeepers, he's one of them
"Such was the confidence of Aston Villa's play at Stamford Bridge that their worst moment ended up being their most admirable