The Gunners’ hopes of finishing in the top four this season took another blow as they were well-beaten by Tony Pulis’ men at The Hawthorns.
The defeat was Arsenal’s fourth in five outings in the Premier League and left Arsene Wenger’s men with a serious uphill battle on their hands to qualify for next season’s Champions League.
Oxlade-Chamberlain was unable to help Arsenal take anything from the game after another day to forget for the Gunners in the top flight.
And the midfielder admitted that the performance left a lot to be desired.
Speaking to Sky Sports after the game, Oxlade-Chamberlain said: “We’re bitterly disappointed. We’re sorry to the fans. That’s not acceptable for Arsenal Football Club.
“West Brom made it really tough and defended really well. We knew who their danger men were and we failed to stop them.”
Next up for Arsenal is their crunch clash against Manchester City at The Emirates after the international break.
The Gunners finished second in the Premier League and without a trophy last season.
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