Arsenal are leading Stoke City 2-1 at half time at the Emirates Stadium.
The Gunners dominated possession in the opening stages and looked particularly dangerous when going forward.
The hosts took the lead after just five minutes when Aaron Ramsey tapped home after Asmir Begovic parried a Mesut Ozil free kick.
Kieron Gibbs found space for a shot on 25 minutes, but the full-back could only fire his shot over the bar.
The Potters grabbed an equaliser on 26 minutes through Geoff Cameron, who calmly slotted home after Marko Arnautovic had hit the post.
Stoke threatened again on 29 minutes when a long ball through the middle found Kenwyne Jones, but Per Mertesacker did just enough to clear the danger.
Mertesacker then gave the Gunners the lead on 36 minutes with a looping header from an Ozil corner.
