Chelsea handed Arsene Wenger one his most demoralising defeats as Arsenal manager as his 1,000th game ended in a 6-0 rout, and the referee also endured embarrassment at Stamford Bridge.
Chelsea earned their biggest league victory under Jose Mourinho after the leaders raced into a 2-0 lead in just seven minutes through goals from Samuel Eto'o and Andre Schuerrle.
Referee Andre Marriner provided the London derby's big talking point by sending off the wrong Arsenal player on 15 minutes.
Although Alex Oxlade-Chamberlain blatantly handled to keep out Eden Hazard's shot, it was Kieran Gibbs who was dismissed despite his teammate's protests.
Hazard scored Chelsea's third from the resulting penalty, before Oscar netted twice and Mohamed Salah completed Wenger's misery with his first goal for the leaders.
Liverpool hit six
Luis Suarez scored a hat trick as Liverpool twice came from behind to beat Cardiff City 6-3 in the Welsh capital.
The hosts took a deserved lead in the ninth minute when Jordon Mutch curled a left-footed strike into the corner.
Suarez equalised in the 16th minute, slotting home from close range after Glen Johnson's right-wing cross.
Cardiff led again through Frazier Campbell when he netted in the 25th, before Liverpool came back with Martin Skrtel poked home in the 41st minute.
Suarez grabbed his second goal on the hour mark before Daniel Sturridge added the fifth in the 75th.
Mutch headed in in the 88th minute, and Suarez completed the rout in stoppage time.
Yaya scores hat-trick
Yaya Toure scored a hat-trick as Manchester City brushed aside last-place Fulham 5-0 to keep pace in the Premier League title race.
Toure converted two penalties in the 26th and 54th minute, both times after fouls by Fernando Amorebieta who was sent off after the second.
Toure curled in his third goal in the 66th minute before being taken off to a standing ovation.
Fernandinho fired in the fourth in the 84th and Martin Demichelis completed the rout four minutes later as the hosts climbed above Arsenal into third place.
City trail leader Chelsea by six points, but have three games in hand.
Rooney on song
Manchester United striker Wayne Rooney lobbed West Ham's goalkeeper from the halfway line and scored another from close range to give the struggling champions a 2-0 victory.
Rooney thrived in Van Persie's absence, rising to third on the club's all-time scoring leaderboard, 37 goals behind Bobby Charlton's record 249.
Everton kept up the pace in a race for a European berth following a 3-2 home win over Swansea after goals from Baines, Lukaku and Barkley.
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.