Arsenal held off a second-half comeback from West Ham United to claim a 2-1 victory at Upton Park and keep their top-four hopes alive in the Premier League.
The Gunners scored two goals in a little over two minutes at the end of the first half to take control of the game, with Santi Cazorla converting from the spot after being brought down, before Danny Welbeck tapped home his side's second.
Cheikhou Kouyate pulled a goal back for the hosts less than 10 minutes after the restart with a header which deflected beyond Wojciech Szczesny and into the back of the net.
Despite pressing for an equaliser the Hammers, were unable to find a way through as Arsenal held out to take all three points.
Here, Sports Mole takes a look back at an entertaining London derby clash in the East End.
Match statistics
WEST HAM UNITED
Shots: 13
On target: 4
Possession: 57%
Corners: 7
Fouls: 12
ARSENAL
Shots: 15
On target: 7
Possession: 43%
Corners: 8
Fouls: 13
Was the result fair?
In what was a hugely entertaining contest at Upton Park, a draw probably would have been a just result on the back of both sides' efforts across the 90 minutes. That said, Arsenal showed real mental strength to see the game out after being pegged back to 2-1, and were able to pick up the three points which lifts them above today's opponents in the league table.
James Tomkins missed a glorious chance shortly before the Gunners' late double at the end of the first half, which could have changed things completely, as too could have Alex Song's volley which was ruled out for offside. The second 45 minutes was mainly a case of the visitors hitting United on the break to create chances, with Adrian being called into action on numerous occasions. In the end it was a decent enough performance from Arsenal, however, which sees them win their ninth successive match against their London rivals.
West Ham United's performance
It is quite telling that West Ham completed more passes (293) than their opponents (209) this afternoon, as they looked for an equalising goal for the best part of 35 minutes. Sam Allardyce will be more than happy with what he saw from his side this afternoon, particularly after falling two goals behind with just minutes to go until the half-time interval. The Irons could quite easily have dropped their heads and rolled over from that point, but Kouyate's headed goal - the 13th time West Ham have found the net in that fashion this season - seemed to change everything.
Having made five changes to his side, bringing in star men Alex Song and Diafra Sakho from the defeat at the hands of Chelsea last time out, Allardyce saw today's game as a real chance to consolidate a place in the Champions League berths heading into the New Year. It was not to be in the end, but that certainly cannot be blamed on a lack of trying. The Hammers have a nice run of fixtures on the whole to start off with in 2015, and if they can take their second-half performance into those fixtures they will have real hope of playing European football next season.
Arsenal's performance
As already touched on, what will please manager Arsene Wenger more than anything on the back of this win was the mental strength shown by his side. In their last two outings on the road Arsenal have scored twice but still failed to pick up all three points. That says a lot about their defence more than anything, but with Laurent Koscielny back in the heart of things this afternoon the Gunners looked steady once more.
Rather worryingly, despite the return of the Frenchman, the North London outfit have now gone five games without keeping a clean sheet. They certainly know how to find the net having now failed to score in just one of their last 12 away games, although if they are to push on and win three successive matches for the first time this term when they take on Southampton next week, then they must tighten up at the back. Overall Arsenal supporters will go away more than happy after seeing their side claim a huge victory at Upton Park, yet there is still work to be done if the Gunners are to push on both domestically and in Europe.
Sports Mole's man of the match
Santi Cazorla: A fine showing from the Spaniard in the middle of the park and a goal to show for his efforts, too, which he himself won after bursting into the penalty area. He did well to control the tempo of things, which helped his side on their way to an impressive win.
Biggest gaffe
Even without the benefit of hindsight it was clear to see at the time that Tomkins's first-half volley which was blasted over the bar could come back to haunt the home team. Two goals in the next five minutes from Cazorla and Welbeck proved that, although the returning centre-back produced a solid performance on the whole on his return to the starting lineup.
Referee performance
Neil Swarbrick had two key decisions to make across the 90 minutes, both of which came in the first half. He got both of them spot on, too, first ruling out Alex Song's volley with a number of West Ham players stood in an offside position, before awarding Cazorla a penalty after he was tripped by Winston Reid. Home fans were left unhappy with the decisions, although the man in the middle appeared to get both correct.
What next?
West Ham United: The Irons host West Bromwich Albion on New Year's Day looking to put today's disappointment behind them.
Arsenal: Wenger's charges travel to face Southampton, meanwhile, in another meeting between two sides battling it out for a place in the Champions League next season.