West Ham United 1-3 Arsenal
Barclays Premier League
West Ham United were undone by a quick-fire Theo Walcott double, as Arsenal came from behind to secure all three Barclays Premier League points at the Boleyn Ground on Boxing Day.
After an eventful first half ended goalless, the Hammers seized the initiative inside 50 second-half seconds, when Carlton Cole scored for a second successive league outing.
But having squandered chances to add a second, the afternoon then turned sour for the hosts, as Walcott struck twice in four minutes, before substitute Lukas Podolski sealed the points with 12 minutes to play. Defeat leaves the Hammers in 19th spot, while Arsene Wenger's men return to the summit of the Barclays Premier League.
The Hammers had earlier shown plenty of promise in a bright start, with Matt Jarvis a menace down the left. In the absence of Ravel Morrison, sidelined with a groin problem, Mohamed Diame took up his more familiar central position, with Joe Cole stationed on the right.
But the Gunners carved out the first chance of note, as Bacary Sagna's right-wing centre looked perfect for Olivier Giroud, but having squeezed between James Collins and Tomkins, the centre-forward could get no purchase on his header.
At the other end, Mark Noble directed a free-kick toward the angle of post and bar, but Wojciech Szczesny turned it away comfortably enough.
With little more than quarter of an hour played, Arsenal threatened once more, this time from a corner. The set piece was only cleared as far as Santi Cazorla, whose header from 18 yards forced Adrian into a smart stop.
With 25 minutes gone and from 25 yards out, Diame tried his luck and though Szczesny juggled his effort, he gathered safely at the second time of asking.
Moments later and Aaron Ramsey's clever through ball picked out Walcott, but he miscued, volleying tamely into the side-netting.
Arsene Wenger's men continued to press and twice went close in the 33rd minute. Adrian was relieved to see Cazorla's long-range drive fizz just over the bar, before Giroud dragged wide, having been played through on goal.
Unscathed thus far, Sam Allardyce was then forced into an early switch, as an injured Collins was replaced by Razvan Rat. The latter slotted in at left-back, with George McCartney deputising at centre-half.
As the first half drew to a close, chances came and went at both ends. For the visitors, Mikel Arteta saw a well-struck half volley fly just past Adrian's right-hand upright, while Giroud was unable to convert Kieran Gibbs' low centre.
Sandwiched between those scares, West Ham very nearly pulled off a well-worked set-piece routine. Mark Noble dinked a free-kick into the path of Kevin Nolan, but faced with the onrushing Szczesny, he failed to make meaningful contact.
Incredibly, West Ham were ahead within just 48 seconds of the restart, with Carlton Cole the beneficiary of Szczesny's blunder. The Arsenal stopper spilled Nolan's 18-yard drive, handing Cole the simplest of chances to fire the Hammers in front, one that he gratefully gobbled up.
Thereafter, West Ham passed up three excellent opportunities to press home their advantage. Having beaten the offside trap, Jarvis fired straight at Szczesny, before Joey O'Brien headed Diame's cross narrowly wide of the far post. Cole then had a second goal in his sights, but skewed Rat's pinpoint centre the wrong side of Szczesny's near post.
Fortunate to still only be a goal behind, Arsenal themselves went close on the hour, with Adrian first repelling Cazorla's effort, before blocking Mesut Ozil's rebound too.
But the Gunners were not to be denied, as Walcott struck twice in the space of four minutes to turn the game on its head. With 68 minutes gone, he cut inside onto his left foot, before seeing his drive squirm through legs and then the hands of Adrian.
Three minutes later and the No14 was celebrating once more. Gibbs' pacey cross flicked off the head of Tomkins at the near post, before Walcott stole in to power a bullet header beyond Adrian.
Much like last season, there was to be no reprieve for the hosts, as Podolski all but put the contest to bed. Collecting Giroud's lay-off, the German frontman fired emphatically into the corner to make it three and consign the Hammers to successive league defeats.
West Ham United: Adrian; O'Brien (Demel 64), Collins (Rat 37), Tomkins, McCartney; Noble, Diame; J Cole, Nolan (Taylor 75), Jarvis; C Cole
Subs: Jaaskelainen, Collison, Maiga, Diarra
Goal: C Cole 46
Arsenal: Sczcesny, Sagna, Gibbs, Mertesacker, Vermaelen, Arteta, Ozil (Flamini 81), Walcott, Ramsey (Podolski 65), Cazorla, Giroud (Bendtner 84)
Subs:Fabianski, Monreal, Jenkinson, Gnabry
Goals: Walcott 68, 71, Podolski 78
Referee: Phil Dowd