It was Arsène Wenger's Travis Bickle moment. The Arsenal manager turned on a newspaper reporter and asked: "Are you looking at me?"

For some managers, especially in the days before television cameras, a blow-out at a journalist would be nothing out of the ordinary. But this was Wenger, a man more likely to serve his players chips and lager than to get in a public row with the press. The same press whose efforts he usually treats with the good-humoured detachment of a charismatic schoolteacher presiding over a class of unremarkable students.

To summarise, Monday morning's newspapers had made grim reading for Wenger following Saturday's FA Cup fifth-round elimination to Blackburn Rovers. Of all the ink spilled he took particular exception to The Sun's back page lead that he was to be offered a two-year extension to his current deal, which expires next summer.

Wenger's contract situation, and the possibility that it may be extended once more, lies at the heart of Arsenal's future. The theory is that his summer signings and his start to next season will be critical in the board's attitude to this monumental decision. The Sun story stated only that Arsenal were "preparing to offer" Wenger a two-year extension. The headline "Wenger's new deal" did not have the mocking tone that Wenger later said he detected.

But this was a strange day for Wenger, a man upon whom the adjective "urbane" has been lavished more times than any other manager on these shores. Having angrily rejected the chance to discuss Saturday's game in relation to tonight's Champions League tie with Bayern Munich, his feelings ran away with him.

Asked about the story in The Sun, he replied: "That is the wrong information. I think I work for 16 years in England and I think I deserve a bit more credit than wrong information that has only one intention: to harm. If it is good information which comes from nowhere it is all right, but this is wrong information that comes from nowhere and it is completely wrong."

He then turned to the Daily Mail reporter Neil Ashton, waiting with the rest of the newspaper reporters for our separate press briefing. The following exchange ensued.

Wenger: "I look at you not because you give information – I don't know if it's you. I don't know where the information comes from. Why do you look at me?"

Ashton: "Me? Because it is your press conference."

Wenger: [ironically] "OK, oh, thank you. I just thought you had given this information out."

Ashton: "No, I am looking at you because it is your press conference."

Wenger: "Oh, OK, thank you very much [sarcastic]."

As a reporter with a high profile on his own newspaper, and the presenter of the Sunday Supplement discussion show on Sky Sports, Ashton will undoubtedly have come to Wenger's attention before. But it would be a leap of imagination to assume he is now filing stories for a rival newspaper.

This was a peculiar departure, for those who have watched Wenger over the years, especially on the occasions he has diffused difficult situations with humour, or ribbed the press – justifiably much of the time – for our readiness to proclaim a crisis. There is no wish to see a manager who has achieved as much as Wenger, and done it in such style, pushed into a corner but here he was fighting back like a man who has lost his patience.

Particularly unusual was the nature of the story which Wenger protested against. You could imagine him taking issue with a story that suggested he was on his way out. But one that said he was to stay at Arsenal longer? "The lie is targeted to hurt," he said later in his press briefing. "It's easy to say people are not happy and on top of that say 'he [Wenger] is extending the contract'."

There are some at the club who believe that he should take the press to task for stories more often, in the way that Sir Alex Ferguson does. They feel that at times Wenger is too conciliatory for his own good. Certainly, there is nothing wrong with some straight-talking but it was the random nature of his outburst that was so puzzling.

At this point it should be said that Wenger is one of the most affable, approachable managers of them all. He never ducks a question and accepts that when things go wrong criticism is inevitable. "You can criticise me and say I'm a bad manager," he said on Monday. "I'd never come back to you on that." But what seems particularly tender for him at the moment is the issue of his future.

When he goes into his final year of his existing deal next season, the question of whether he stays beyond June 2014 will hang over everything the club does. The longer it goes unresolved, the more uncomfortable it will be for both parties. Conversely, if he does sign an extension then there will be an inevitable expectation of an improvement from fans.

After the television cameras were turned off, and in a more reflective mood on the issue of his contract, Wenger wanted only to say that he had been doing the job a long time. "I will have completed 30 years [next year] without interruption at the top level," he said. "Football demands a lot of commitment. I may not be quality, but commitment? For sure."

Quality? Of course he is. His achievements will rank among the finest of any manager in the English game no matter how it ends. Did it hurt him, he was asked, that his history was overlooked? "No. I'm just hurt that it [Saturday's result] happened to us," he replied. "That's the real hurt."

Three key confrontations: Arsenal v Bayern

Per Mertesacker v Mario Mandzukic

The Germany defender will have a tough job shackling Croatian striker Mandzukic, who has scored six goals in his last five games.

Jack Wilshere v Bastian Schweinsteiger

Both are driving forces in midfield, looking to establish a quick supply line from defence to attack.

Oliver Giroud v Daniel van Buyten

Giroud has been more clinical recently, and could cause the 35-year-old some problems.