Jose Mourinho extended his unbeaten record against Arsene Wenger to 12 matches as Chelsea battled to victory over Arsenal.
Diego Costa continued his excellent scoring record by notching his ninth goal in seven Premier League appearances.
Former Arsenal midfielder Cesc Fabregas provided the assist for Costa’s goal to ensure it was a happy afternoon for the Spaniard after Eden Hazard had opened the scoring.
Hazard both won and converted his penalty to give Chelsea a first half advantage and extend their lead at the top of the table to five points.
The Gunners failed to register a single shot on target before the 90th minute, despite enjoying a decent amount of possession, and were outmanoeuvred by Mourinho’s men.
The match was delayed by fifteen minutes due to a flare being set off by an entrance to the away end.
Alexis Sanchez was denied a chance by an onrushing Courtois, who was flattened by the Arsenal winger for his troubles.
Gary Cahill earned himself a booking for a poor challenge on Sanchez that led to Mourinho and Wenger being involved in a heated exchange on the touchline.
Courtois was still suffering from his accidental clash with Sanchez and was replaced by Petr Cech just after the 21st minute. Courtois was taken to hospital.
Chambers was then booked, for the fifth time this season, for a challenge on Eden Hazard and now misses Arsenal’s next match against Hull.
Hazard was involved again moments later as he brilliantly skipped past three Arsenal defenders including Laurent Koscielny who subsequently brought him down and was booked.
Hazard casually rolled the penalty into the corner with Szczesny diving the wrong way.
Hazard caused Arsenal numerous problems and his drilled ball across the box deflected off Flamini to force Szczesny into an excellent save.
The Gunners were then incensed that they weren’t awarded a penalty after Fabregas blocked a Wilshire shot with his hands.
Costa scored Chelsea’s second by looping the ball over Szczesny after an excellent ball over the top of Arsenal’s backline from Fabregas.
Costa then missed an open goal in stoppage time that could have been his tenth goal of the season.