The boys remain unbeaten away from home this season after a hard-fought victory over Crystal Palace on Saturday.
Mikel put the Gunners in front from the spot two minutes after half-time before he was sent off after a collision with former Gunner Marouane Chamakh.
But Olivier headed home late on to keep Arsenal top of the Premier League. You can see a bitesize clip of the game by clicking the play button above.Copyright 2017 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source