The television cameras were switched off, there had been a moment or two to gather his thoughts and then Arsène Wenger started to speak from the heart and defend his record.

It was as if that controversial banner raised in the visiting end after the final whistle – “Arsène, thanks for the memories, but it’s time to say goodbye” – and the three terse responses the Arsenal manager had served up on the subject minutes earlier, when he made it abundantly clear that his departure was not up for discussion, were playing on his mind.

The first question that followed was about Arsenal going through a recurrent theme season after season – poor form, an avalanche of criticism and then the team goes on a run. Wenger gave the impression that he was not really listening. Not because he was being rude or evasive, but because he was still turning over in his head the idea that a group of Arsenal supporters had chosen to hold aloft a message at the end of a match his team had won telling him that he had outstayed his welcome.

“Look, in the last 15 years we are qualified for the last 16 in the Champions League. Give me another club who has done that,” Wenger said. “I think we have shown extreme consistency and that’s all we can do. We’ve had ups and downs in the league – yes, it’s true, but you only come back again when the spirit is strong and healthy and united inside the club. And I think if you have shown such a consistency it’s because we have that at the club. We have values and we respect them.”

Asked whether he wonders what more he can do to answer the fans’ criticism, Wenger replied: “I can do my job. I do my job with total commitment, I would like you to live with me and see for seven days what kind of work we produce and you will see that it is total commitment.”

Wenger insisted that he was not hurt –“No. Honestly, no” – but he was kidding nobody. Two wins in four days, two clean sheets, a place in the knockout stages of the Champions League secured and the Arsenal manager was still talking about supporter unrest. It was bound to niggle him.

It took a question about whether Wenger considered himself to be tactically flexible, in light of a few tweaks that he made in the second half against West Brom, to lighten the mood. “I started to manage a team at the top level in 1983,” Wenger said, smiling. “If I am completely useless tactically, I am a genius. I can hide it very well.”

With that the Arsenal manager turned on his heel and was gone. Arsenal had a much-needed three points in the bag, another three injured players waiting on the coach – Nacho Monreal limped off with a knee problem, his replacement, Kieran Gibbs, hurt his ankle and Alex Oxlade-Chamberlain also took a blow to his knee – and Wenger had said his piece, 121 seconds from start to finish.

Once the dust settles on his latest brush with the naysayers, Wenger might reflect that, as well as the result, there were several positives for Arsenal here. Laurent Koscielny made a successful return after eight weeks on the sidelines, Olivier Giroud suffered no negative reaction on his first Premier League start of the season, Danny Welbeck ended a run of six Arsenal games without a goal and Santi Cazorla was a joy to watch.

Arsenal being Arsenal what happens next is anyone’s guess. They host Southampton on Wednesday night – Wenger is unsure whether any of the trio who have added their names to the injury list will be fit – and it is safe to say that Ronald Koeman’s side will represent a much tougher proposition than a pedestrian Albion team.

Doom and gloom has descended again at The Hawthorns. Alan Irvine, the head coach, was subjected to chants of “You don’t know what you’re doing” and boos greeted the final whistle after Welbeck’s goal condemned Albion to a third successive defeat. It is now 360 minutes since an Albion player scored a league goal.

Saido Berahino headed against the crossbar late on and was unfortunate to be flagged offside early in the second half but otherwise Albion created little and gave Emiliano Martínez – who was making his first Premier League start for Arsenal – a stress-free afternoon in goal. West Ham visit The Hawthorns on Tuesday night and Irvine is under no illusions about the need to stop the rot. “It’s a huge game,” the Scot said.

Man of the match Santi Cazorla (Arsenal)