Chelsea put Arsenal's top-four challenge on ice with a 2-1 win over their London rivals at snowy Stamford Bridge on Sunday.
Rafael Benitez's side raced into a two-goal lead within the first 16 minutes thanks to Juan Mata's strike and a Frank Lampard penalty and then weathered the storm in freezing temperatures as Arsenal threatened a second half fightback.
Theo Walcott's cool finish gave Arsenal hope of salvaging a point, but the Gunners now languish 11 points behind third placed Chelsea and six adrift of fourth placed Tottenham, who could extend that advantage when they face Manchester United later on Sunday.
Arsene Wenger's side have won only one of their last five matches and another frustrating season looks set to be reduced to a struggle to qualify for the Champions League.
With heavy snow settling across London throughout Sunday morning, it was briefly feared the match may have to be postponed, but it went ahead as scheduled, giving Chelsea a chance to cure their home sickness.
The Blues had won just one home league game under interim boss Benitez and recent defeats at the Bridge against QPR and Swansea had further strained the Spaniard's already frosty relationship with Chelsea's supporters.
Arsenal desperately wanted to take advantage of that mutinous atmosphere, but, not for the first time in his short Arsenal career, French striker Olivier Giroud failed to rise to the challenge, firing well wide from a good position in the early stages.
It proved a costly miss as Chelsea took the lead in the sixth minute thanks to a goal laced with controversy.
Ramires won possession from Francis Coquelin, but it appeared the Chelsea midfielder caught his Arsenal counterpart on the foot in the process.
With Wenger and Arsenal's players appealing in vain for a foul, Cesar Azpilicueta lofted a pass towards Mata and the Spanish midfielder ran clear of the woefully out-of-position Bacary Sagna before firing his shot into the roof of the net.
Fuelled by a burning sense of injustice, Arsenal flooded forward in search of an equaliser and Santi Cazorla's stinging strike from long-range forced a fine save from Petr Cech.
But Arsenal's task got even harder in the 16th minute when their defensive frailties were exposed yet again.
Standing statuesque on the edge of the penalty area, Arsenal's defenders allowed Mata to clip a pass to the unmarked Ramires and the Brazilian was sent crashing to the turf by Szczesny's despairing lunge.
Referee Martin Atkinson gave a penalty and Lampard calmly sent Szczesny the wrong way from the spot to double Chelsea's lead, giving another reminder of his value as the club's hierarchy debate whether to offer the England international a new contract.
Ramires could have put the result completely beyond doubt before half-time, but the Brazilian blazed over after skipping past a powderpuff challenge from Kieran Gibbs.
Arsenal had been woeful in the first half, yet they were a team transformed after the break.
Showing more desire and vision in the final third, they created early chances for Per Mertesacker and Giroud and, although neither converted, it was enough to change the momentum of the match.
Their pressure was rewarded when Walcott, playing for the first time since agreeing a new contract, pounced in the 58th minute, sprinting onto Cazorla's pass and dispatched a clinical finish past Cech.
Chelsea had blown a two-goal lead against Southampton in midweek and the Blues' nerves were clearly jangling as Arsenal probed for an equaliser.
Substitute Demba Ba should have eased the anxiety in the closing stages when the striker's shot was cleared off the line by Thomas Vermaelen, but Chelsea were just able to hold on.