Chelsea moved five points clear at the top of the Premier League table with a 2-0 win at home to Arsenal on Sunday.
An Eden Hazard penalty put the Blues ahead, before Diego Costa continued his outstanding goal-scoring form to put the game to bed with 12 minutes to play.
The match was full of incident, with a minor altercation between Arsene Wenger and Jose Mourinho on the touch-line prompting much debate from watching fans. But on the pitch, the game changed when Hazard was fouled by Laurent Koscielny and the Belgian international dusted himself off to dispatch the spot-kick.
Arsenal had a valid penalty appeal turned down when their former player Cesc Fabregas blocked a shot with his arm in the area. And the Spaniard would have a bigger part to play when his outstanding long pass was controlled brilliantly by Costa before he scored what proved to be the last goal of the game.