Albion were beaten by a late Oliver Giroud header to give the Baggies the Boxing Day blues.
Here's what the papers had to say. Click on the link to read the full report.
An Oliver Giroud header three minutes from time delivered the knockout blow to break West Bromwich Albion’s brave Boxing Day resistance.
Ben Foster had been equal to everything, but could not extend enough to keep out the Frenchman’s looping header.
It was no more than the Gunners deserved, but the timing of the goal was cruel on the visitors who had defended for their lives.
This new-look Albion side have proved this season they can threaten in the final third, and score plenty of goals to boot, but this performance confirmed that Pulis has not abandoned his core beliefs.
Difficult to break down, Albion soaked up pressure and frustrated the Gunners, who so desperately needed all three points after back-to-back defeats.
Jonny Evans was back in the starting line-up after missing the last two games with a calf strain, replacing Jonas Olsson at the heart of defence.
Arsenal meanwhile, were ravaged with injuries. Theo Walcott, Alex Oxlade-Chamberlain, Santi Cazorla, Shkodran Mustafi, and long-term absentees Per Mertesacker and Danny Welbeck were all out, which persuaded Arsene Wenger to hand Giroud his first league start of the season as he attempted to combat Albion's physicality. It was a move that eventually paid off.
Just as they did at Chelsea, West Brom lined up with seven men, including Foster, behind the ball when they were defending and it proved to be similarly difficult for the hosts to get past them.
Arsenal, and in particular Sanchez, came alive after the restart and it took a combination of Foster and the post to prevent Wenger’s men from taking the lead before the hour mark.
But, with Theo Walcott and Alex Oxlade-Chamberlain both out injured, Giroud was handed his maiden league start of the season and, after a frustrating afternoon, the Frenchman headed home an 87th minute goal to secure a 1-0 win.
Until then, Tony Pulis' side had kept Arsenal at bay, with goalkeeper Ben Foster pulling off a string of saves as the Baggies looked set to leave the Emirates Stadium with a well-deserved point.
Giroud would ruin that as he met Mesut Özil's cross after tussling with Gareth McAuley and Wenger was quick to back the former Montpellier man.
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