Arsène Wenger can never exhaust his levels of credit in English football, but there are an increasing number of occasions, such as in the media room at Stamford Bridge on Sunday, when he seems determined to give it a damn good go.

Great admirers of “The Professor” actually found themselves shaking their heads in sorrow and dismay as they jotted down his latest unsustainable explanation for a damaging Arsenal setback.

It was not that Wenger was making excuses for a defeat; every manager has done that since time began.

No, what increasingly distinguishes a Wenger tirade is the moralising tone. And while that was once acceptable, and justifiable, in the occasional outburst at roughhouse methods from Bolton Wanderers or Blackburn Rovers, it has now reached the point where Wenger risks becoming an unpopular parody of himself by preaching from on high.

To listen to him this season has been to see parallels with the Tony Blair portrayed by Matthew Parris in this paper. Writing about the former Prime Minister and his recent appearance at the Chilcot inquiry, Paris described Blair as “a Manichean, or dualist”.

Blair’s universe was best understood, he observed, as a struggle between forces of good and evil. “Once you understand this, there is no arguing with him,” he wrote.

It has become a bit like that with Wenger; he is so convinced that Arsenal’s way of playing is the right way, how the game was always meant to be played, that things such as the number of goals are dismissed as mere details in his bigger, philosophical struggle.

“So what if we lost 2-0? We were superior,” was the tone of his responses on Sunday. And that, he believes, should win the argument.

Wenger’s world has become so black and white, so divided between right (Arsenal) and wrong (everyone else except, perhaps, Barcelona) that conquerors of his team are never worthy but sneaky or brutal. At best they are grudgingly called “efficient”.

There can be few teams left in the Premier League who have not been derided by the Frenchman this season when, even among the best, Manchester United have been called “anti-football”, Aston Villa attacked for their “long-ball game” and now Chelsea dismissed, unjustifiably, for dullness and fouling.

Chelsea may have acquired an unhealthy streak of cynicism under José Mourinho but there was nothing untoward about Sunday’s performance; no dark arts.

As for the possession count that Wenger inflated from 58 per cent to 70 in Arsenal’s favour, he failed to make allowance for the fact that Chelsea may have been happy to concede the ball, knowing how easy their opponents would be to expose on the counter-attack.

While it might be simple to dismiss the comments as the sour grapes of a bad loser, which Wenger readily admits he is, this matters because the philosophy can hardly be a healthy one to disseminate among the players.

The last thing that Gaël Clichy, Bacary Sagna and Theo Walcott need to hear is that all their good football entitles them to better results. It is precisely the opposite — a flash of underdog spirit, a grasp of the hard realities — that they need to take into games against Chelsea and United.

It was the predictability both of the Arsenal performance, and the post-match complaints, that made this so depressing. We lovers of football look to Wenger for enlightenment, not for carping and specious post-match analysis.

Wenger’s particular beef this season has been the cynical fouls — he calls them “tactical” — in the middle of the pitch and they can be a huge irritant to us all. But there were few from Chelsea on Sunday. As for Arsenal, perhaps they might have spared themselves two heavy defeats with some challenges around the halfway line.

None of us wants to see Wenger abandon his thrilling philosophy, or weaken in his determination to play the beautiful game. That includes the most frustrated Arsenal fan, even if they would prefer the manager to sign a few more streetwise, hardened players.

But his pursuit of that ideal, his intelligence and his record does not mean that his methods should go unchallenged. And there’s the rub.

There are those who wonder if Arsenal’s main problem is not the lack of a deputy for Robin van Persie but the absence of anyone within the club to confront the manager; someone to question why he has not tried to sign a centre forward, to insist on more defensive drills, to say that the system should be altered so that the team are not lambs to the slaughter against Chelsea or United.

Every club needs freshening up. Sir Alex Ferguson does it by leaving almost all the daily training to his assistants. He has conducted fewer than a handful of sessions in the past decade.

Is it not time for Wenger, whose voice is heard day after day by his players, to bring a strong new assistant on to his coaching staff? To explore other ways to skin the cat?

Let those shrill terrace critics at the Emirates who call for Wenger’s head any time there is a blip not take this as some kind of encouragement; the club, despite the heavy defeats of the past two weekends, remain so indebted to Wenger’s brilliance, and dependent on it, that to wish his departure any time soon remains unthinkable.

But a fifth season without a trophy is now highly likely, given that the Champions League is a long shot. And Wenger’s frustration was evident on Sunday to the point where he appeared ready to self-combust.

Standing just in front of the dugout, he was exasperated for the entire 90 minutes, stomping around, reacting to every little foul by Chelsea. When Didier Drogba gently grabbed at Clichy in a nothing incident, he looked ready to erupt as though the Chelsea player had committed an outrageous affront.

The lack of proportion followed him into the media room where he talked as though there was only one true way to play the game — the Arsenal way — but it made him sound not wise, or visionary, but eccentric.

Arsenal are not good enough to compete for the big prizes — and until Wenger addresses the hole in his defence, there will also be one in his moral arguments.