Arsenal striker Alexandre Lacazette celebrates scoring against Chelsea (AFP)
Arsenal eased their relegation fears and lifted the pressure on beleaguered boss Mikel Arteta with a much-needed 3-1 win against Chelsea on Saturday.
Arteta's side sat just three points above the relegation zone before kick-off at the Emirates Stadium after their worst start to a season since 1974-75.
But the Gunners produced their best performance this term to out-class their London rivals.
Alexandre Lacazette's controversial penalty opened the scoring before Granit Xhaka's superb free-kick increased Arsenal's lead before half-time.
Bukayo Saka bagged Arsenal's third goal after the break as they won in the Premier League for the first time in eight games stretching back to November 1.
Tammy Abraham's late strike was no consolation for woeful Chelsea, who missed a penalty through Jorginho in the final moments.
Moving six points clear of the bottom three will buy Arteta a little breathing space following talk he was in danger of the sack after just a year in charge.
Arsenal have only been relegated from the top flight once in their history, in 1912-13.
With matches against Brighton and West Brom coming next in their Christmas schedule, Arsenal have a chance to climb to a healthy league position heading into 2021.
Having won the FA Cup final against Chelsea in August, Arteta has now delivered two major blows to Blues boss Frank Lampard this year.
Chelsea would have gone second with a victory, but instead they remain six points behind leaders Liverpool after a third defeat in their last four league games.
Lacklustre in attack, short of drive in midfield and bereft of a cutting edge up front, Chelsea's £200 million ($267 million) pre-season overhaul is yet to pay off.
Lampard has only 48 hours to lift Chelsea's flagging spirits before they are back in action against Aston Villa on Monday.
Arteta suffered a pre-match blow when Gabriel was ruled out for three matches as he self-isolates under coronavirus protocols.
Pierre-Emerick Aubameyang started on the bench as he battles with a calf injury and a poor run of form, yet Arsenal didn't miss their captain or Brazilian defender Gabriel.
Although Chelsea midfielder Mason Mount curled a free-kick against the outside of the post, there was no doubt who was on top.
Arsenal made the breakthrough in the 35th minute when Kieran Tierney got across Reece James into the Chelsea area and tumbled under the slightest contact from the panicked defender.
Michael Oliver's debatable decision to award a penalty survived a VAR review and Lacazette sent Edouard Mendy the wrong way from the spot for his sixth goal of the season.
It was no more than Arsenal deserved for a vibrant first half and Arteta was celebrating again in the 44th minute.
Xhaka has been much-maligned at Arsenal, with the Swiss midfielder's most recent faux pas coming when he was sent off in a defeat against Burnley.
N'Golo Kante fouled Saka and Xhaka did his bit to get back in favour when he whipped a brilliant 20-yard free-kick over the Chelsea wall and into the top corner.
Lampard sent on Jorginho and Callum Hudson-Odoi for Timo Werner, whose goal drought now stretches to 10 games, and Mateo Kovacic.
But the switches failed to spark lethargic Chelsea into life and Arsenal struck again in the 56th minute.
Hector Bellerin and Emile Smith Rowe combined to send Saka into the area and his cross-shot looped over Mendy into the far corner.
Abraham converted Hudson Odoi's cross from close range in the 85th minute to spark a late Arsenal wobble.
Pablo Mari's foul on Mount gave Chelsea a stoppage-time penalty, but Jorginho missed for the third time this season as Bernd Leno kept out the Italian's weak effort.
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