Following a sublime through pass by Nemanja Matic, fellow January recruit Salah slid home the sixth of the day for Chelsea, only three minutes after replacing Brazil's Oscar.

Leaders Chelsea were largely helped by the early sending off of Arsenal defender Kieran Gibbs, who mistakenly received red after Alex Oxlade-Chamberlain handled the ball on the line.

Oscar (twice), Eden Hazard, Andre Schurrle and Samuel Eto'o were on target for Jose Mourinho's side.

Salah goal