Yaya Toure scored a hat-trick including two penalties as City wrapped up a punishing 5-0 win over bottom club Fulham and Luis Suarez's prolific run continued with three goals as Liverpool twice came from behind to thrash Cardiff City 6-3.
The goals were spread about for Chelsea as Samuel Eto'o, Andre Schuerrle, Eden Hazard, Oscar (2) and Mohamed Salah were on target for the leaders in a match likely to be remembered for a bizarre refereeing blunder as much as Chelsea's cut and thrust.
Official Andre Marriner flashed a red card at Arsenal's Kieran Gibbs for a handball on the goalline by Alex Oxlade-Chamberlain.
The sending-off did little to affect the destination of the points, however, as Arsenal were already 2-0 down when Gibbs was dismissed and Hazard stepped up to convert the resulting penalty to make it 3-0 after just 17 minutes.
Chelsea stayed four points clear of Liverpool in second, the Londoners having played a game more, with Manchester City six adrift of Chelsea in third but with three games in hand. Arsenal slipped to fourth.
Everton moved up to fifth with a 3-2 win over struggling Swansea City and Norwich City improved their chances of avoiding the drop by beating relegation rivals Sunderland 2-0, their second a stunning volley from Alex Tettey.
West Bromwich Albion lost 2-0 at Hull City and Newcastle United's Papiss Cisse scored in stoppage time to inflict a painful 1-0 defeat on Crystal Palace.
Image: Chelsea players celebrate after Eden Hazard scored the fourth goal against Arsenal.
Photograph: Richard Heathcote/Getty Images
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