“The size of the game is decided by the number of microphones” – so quipped Arsenal boss Arsene Wenger at today’s (Friday) press conference ahead of tomorrow’s clash with Chelsea.

Peering across the multitude of microphones to sports reporters and television crews – including from Germany and France – who had gathered at the club’s London Colney training grounds, Wenger was clearly anticipating a barrage of questions about his famously fractious ‘relationship’ with his Chelsea counterpart, José Mourinho.

Unusually at the conference, there was even a bit of banter between the unflappable Wenger, and the Press Association’s Jim van Wijk.

The latter asked: “Is it difficult sometimes when managers are in the heat of the moment and on the side of the pitch to restrain yourself, or do you have to say to yourself, ‘come on Arsene, hold back’?

Wenger said: “I advise you one thing, manage a team for a year and come back to the press conference and we talk about it.”

He laughed when Van Wijk replied: “We won the university cup. I managed the university [but] I got sent off several times.”

Wenger agreed that there was too much media interest in his relationship with Mourinho, and added that as people were more interested in watching football, ‘all the rest is secondary’.

He commented: “I focus on what I love, which is football and I respect everybody and focus on what I love, all the rest, doesn’t concern me too much.”

In response to a question about Chelsea’s defence and whether the team is weaker than in previous seasons, Wenger said: “It is too early to judge Chelsea at the moment.”

A question about whether it was ‘strange’ going into a match against a Chelsea side which has lost three out of its last four games in the Premier League had Wenger replying: “No [it is not strange] but it can happen.”

Does he see this as an opportunity to beat Chelsea? “Look for us it’s a big game, don’t forget it is the start of the season and there are only five games played. I don’t consider too much where Chelsea stands at the moment.

“But I focus more on us performing well, with full power, tomorrow morning.”

Asked whether Chelsea was in decline, Wenger said: “I don’t know. I leave that to the specialists, and I take care of my team and my own problems.”

He was also asked about whether goalkeeper Petr Cech, who joined Arsenal from Chelsea in June this year, would be a ‘mole in the camp’ and give fellow Gunners a bit of extra insight on Saturday.

Wenger replied: “Yes, but there is no big secret, other than on the day, perform at your best, and together. Our solidarity, our performances will be more important than what he knows. There is no massive secret in that.”

Wenger said that he expects high intensity, focus and ‘full commitment’ from his team against Chelsea.

Updating reporters on team injuries, he reported that there were no injuries from Wednesday night’s UEFA Champions League match, which Arsenal lost to Dinamo Zagreb (2-1).

On September 15, ahead of that game, a club statement said that Jack Wilshere would have surgery in London in the forthcoming days, and this “will involve inserting a small plate in his left fibula. Jack is likely to be out for approximately three months.”

It was confirmed at today’s conference that Wilshere will have an operation next week, with Wenger admitting, “it is a blow, it is a problem but a short term one only because it doesn’t damage his future”.

Asked questions about resting so many players in Croatia, Wenger said: “In football, you forget cheap excuses, and focus on what matters; on the day, it is the performance of the day. If you want to make a career at the club, without any disappointment, that is not possible.”

Reflecting further upon Wednesday’s loss, he said: “I stand up for my selection, and take responsibility for it. I believe we can repair what happened. It is easier to lose away from home, than at home. Every defeat hurts, but every defeat offers an opportunity to respond in a strong way.”

• Chelsea V Arsenal, Barclays Premier League, Saturday September 19, Stamford Bridge, 12.45pm