Arsenal survived a second-half comeback from West Ham United to clinch a 2-1 win in the Premier League at Upton Park this afternoon.
West Ham made the better start to the match, and thought that they had taken the lead when they found the back of the net just six minutes in, but Alex Song's long-range volley was ruled out as several of his teammates were offside and apparently interfering with play.
The hosts continued to threaten as Cheikhou Kouyate forced a save from Wojciech Szczesny, before Laurent Koscielny had to block a powerful effort from Andy Carroll.
Despite the home side's dominance, it was Arsenal who broke the deadlock when Winston Reid tripped Santi Cazorla in the box, and the Spaniard fired in from the penalty spot shortly before half time.
Arsene Wenger's side doubled their lead only three minutes later when Alex Oxlade-Chamberlain picked out Danny Welbeck with a cross, leaving his England international colleague with a simple tap in at the far post.
Mathieu Debuchy attempted to make it three early in the second half when he tried his luck from 30 yards out, but his effort bounced just in front of Adrian to leave the keeper with a comfortable stop.
The home side got themselves back into contention shortly after as James Tomkins burst towards the Arsenal goal during a quick counter-attack, crossing in for Kouyate to head in and give the Hammers hope.
Arsenal came close to restoring their two-goal cushion just a couple of minutes later as Cazorla tried to power the ball home, but Adrian managed to parry clear.
Both sides continued to press, but it was Arsenal who looked more dangerous in front of goal, with Welbeck almost adding a second following a quick break.
Adrian continued to come under pressure as he made saves to deny Oxlade-Chamberlain and Alexis Sanchez, while Morgan Amalfitano fired just over down the other end.
The visitors continued to try to seal the points in the final minutes, but the West Ham keeper could not be beaten as he kept out another shot from Cazorla, who then fired the rebound high, while Oxlade-Chamberlain curled a shot wide a few minutes later.
Kevin Nolan came close to getting a last-gasp equaliser when he drilled the ball towards goal from 20 yards out, but Szczesny palmed his shot clear before Carroll's follow up failed to test the keeper.
Amalfitano wanted a penalty in stoppage time when he went down under a challenge from Sanchez, while former Gunners midfielder Song curled in a late free kick, but Enner Valencia headed it over.
The result moves Arsenal above West Ham into fifth in the Premier League table, level on points with fourth-placed Southampton.