Alexis Sanchez scored twice as Arsenal climbed above neighbours Tottenham and into fifth place in the Premier League with a dominant display against Stoke.
Laurent Koscielny took advantage of slack marking to head the hosts into an early lead from Sanchez's cross.
The Chile international then finished off a neat move with Tomas Rosicky to double Arsenal's lead before half-time.
Sanchez, 26, added his second goal of the game and 18th of the season from a free-kick shortly after the break.
It proved a relatively routine victory for an Arsenal side and for David Ospina, who retained his place after the 2-0 FA Cup third round win over Hull.
It was the 26-year-old Colombia international's his first Premier League start, with Wojciech Szczesny dropped to the bench following reports he was caught smoking in the showers after the New Year's Day defeat at Southampton.
Stoke were given early warning of Arsenal's intent when Sanchez and Tomas Ros
