By Josh James at Emirates Stadium
Summary
Second half goals from Mesut Ozil, Theo Walcott and Olivier Giroud gave us a much-needed and richly-deserved victory at Emirates Stadium.
After a hard-working display in the first half in which Danny Welbeck missed our clearest chance, we stepped up the tempo after the interval - and blew the Hammers away.
Ozil broke the deadlock from outside the area with a low curling effort, before he turned provider, squaring for Walcott to tuck home our 100th goal of the season.
A spectacular Giroud bender, placed beyond the despairing Darren Randolph, wrapped up the points.
The win moves us back up to fifth place - now the race for the top four can really start in earnest.
Setting the Scene
The big team news was who started in goal. Emi Martinez came in for the injured David Ospina, with Petr Cech also still unavailable.
The Argentine stopper played all three EFL Cup games this season - keeping two clean sheets - but this was his first Premier League outing since 2014, and only his 12th first-team game for the club in all.
The two other changes from Sunday's lineup were also enforced.
Gabriel - who replaced the injured Laurent Koscielny at half-time against Man City - kept his place from the start, while Mohamed Elneny returned to midfield in place of Francis Coquelin, who was on compassionate leave.
Alex Oxlade-Chamberlain and Aaron Ramsey were both fit enough to be named among the substitutes.
Andy Carroll, with four goals in his last two games against us, led the line for the Hammers.
FIRST HALF
Alexis Sanchez scored a hat-trick at the London Stadium in December, and he was straight into the action here, buzzing around on the left flank and flashing a shot wide in the opening five minutes.
West Ham's first chance came when Michael Antonio was brought down on the edge of the area and Manuel Lanzini curled a free-kick just over the bar.
A Theo Walcott snapshot was easy for Darren Randolph, then the Gunners captain had a penalty appeal turned down, but that aside there was precious little goalmouth area in the opening 20 minutes.
Welbeck squandered our best chance opportunity midway through the half. Alexis clipped in a free-kick and Welbeck was all alone in the area, but the forward completely miscued, air-kicking when he seemed set to break the deadlock.
Walcott's connection was true when he was set free by Welbeck moments later, but it was his aim that was lacking, crashing his shot wide of the near post.
At the other end, every set-piece West Ham won was floated into our area, but each was dealt with without alarm.
The half ended with a flurry of chances. First Hector Bellerin had a shot blocked after being picked out by Alexis. Elneny's follow up shot was deflected over for a corner, which Welbeck headed straight at Randolph.
Walcott's late effort was also snuffed out by the visiting keeper, but it was an encouraging end to the first 45 minutes.
SECOND HALF
We came out for the second period with the same verve in which we finished the first.
Unusually Ozil's touch let him down when Alexis set him up in the box, and James Collins slid in to dispossess him.
Arsenal were knocking at the door, and eventually the pressure told. A clearance fell to Ozil five yards outside the box, and his low curler found its way into the bottom corner.
Our tails were up now. Welbeck had a chance to double the lead after Walcott's jinking run and subtle flick released him on goal, but Randolph was out quickly to deny him.
We kept the pressure on and the second goal duly followed. A wonderful backheel from Alexis found Ozil, who in turn centered first time for Walcott to force the ball home. Breathing space at last.
It was our 100th goal of the season, and number 101 nearly followed immediately.
Alexis followed up some fantastic chest control with a lofted pass to the advancing Bellerin, and the right back's half volley went agonizingly wide.
Martinez had barely called upon in the second half, but he made a good parry to keep out Lanzini with 15 minutes remaining.
It was substitute Giroud who sealed the win in fine style late on. Fellow sub Oxlade-Chamberlain fed the Frenchman inside the area, and he expertly arced home a left-footed curler, giving the keeper no chance.
Nacho Monreal had a strong penalty appeal turned down in injury time, but the Gunners had won with room to spare.
Referee: Martin Atkinson
Attendance: 59961
Copyright 2024 The Arsenal Football Club Limited. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source.