How did you find the experience of writing a book? It was a good exercise for me to reflect on 30 years within football and different experiences. Because I wasn’t regarded as that talented, I always wanted to find out what did it make within me when people said: ‘You’re not good enough.’ And my upbringing ... as my dad sat next to me negotiating a contract and saying: ‘No, no, this is too much’ – he refused to take that money. I was really angry at that time with him but he was sending me messages which were really important moving forward. I look back to those moments and think they had a bigger impact on me than I expected.

Per Mertesacker: ‘It gives you the goose bumps ... on the pitch you see actual joy’ Read more

So how did those experiences shape you as a person and a player? I had a lot of adversity, with being injured, being assessed as the one who would not make it. How my parents stayed relaxed at that stage helped me a lot. You need to make sure you don’t take it too serious at times and that really helped me to refocus on the moment when the opportunity really arrived. I never regarded it as: ‘Oh, here you go, here you have everything.’ That’s the new generation: take, take, take. No, no, no. If you just think it’s about taxis [picking you up and dropping you off], money and credits, that’s the opposite of caring for you.

Has your own story been useful for the academy work you do now? I want to make an impact on young people’s lives and be part of their future no matter what they do because I have seen that all the very talented players at 15, 16 still had very little chance to be successful in football. Football has taught me so much. I want to use that but still make sure there is some reality. You cannot turn the clock back 20 years.

I had a totally different upbringing and background – raised in a small town in Germany. Now I am in London taking care of 180 kids who think they are the 1% who can make it in professional football. How do I manage that? By being myself, being authentic and not lying. So I tell them: ‘You might be the 1%.’ It’s difficult because you have to make judgments.

But if the family thinks football is the only thing you can do in life, then it’ll be difficult to get on with that pressure. Sometimes I get the feeling that some parents really think their son can pay for their pension, especially being in London.

Has the new role been what you expected and what have been the challenges? The amount of staff we have in academies is ... I’ve never seen anything like it. It’s good to take care of the players but sometimes I get confused by the number of people who have an impact on one kid – we’re talking 100 people or more. It’s quite a heavy load. On one hand you’ve got to embrace it and try to get the best people in the academy.

Where does the reward come from for you now? You see the players go to the first team or another club, going to the world – that should be the hall of fame. We shouldn’t just focus on those who make it. A first-team player at Arsenal or, just for the sake of argument, a doctor in America would give me similar reward; that we have impacted a young kid’s life positively and that he would come back and say: ‘Yeah, this has made me a better person.’

Facebook Twitter Pinterest Per Mertesacker became a fan favourite at Arsenal. Photograph: David Price/Arsenal FC via Getty Images

In England people often talk about the lack of pathways for young players. Has Jadon Sancho’s decision to go overseas changed the landscape in academy football here? Yeah, I think so. We have, even from our side, academy players going to other countries. And we take value. So for us this summer was really positive – you had Alex Iwobi going to Everton – a player that established himself in the first team. Then we have Xavier Amaechi, who’s gone to Hamburg and we get a fee and add-ons. Krystian Bielik, who went to Derby, has been a part of our academy. Jeff Reine-Adélaïde goes to France because we knew he wasn’t getting the pathway in the first-team. But he creates value with that move.

What one thing needs to change to make Arsenal world-class again?You really want to build the best connection between players and fans, that everyone feels that this is the best club. So a real culture that everyone trusts each other that we can be world-class again.

Per Mertesacker: ‘Some fans want a selfie but sometimes I want to say: Let’s just shake hands’ Read more

But there are many aspects. My point is that I want to make a world-class academy, that everyone feels we get the best talent towards the first team. The first-team manager right now wants to bring us back to the Champions League.

The new technical director wants to deliver the best recruitment, which the club has not seen for a long time. So everyone has small targets but what I would say is, we want to have the trust and connection from the fans that the people in charge can deliver.

Did Arsenal lose that? Definitely. You could feel that. But still there’s a more positive energy I would say right now than there ever has been. And that has been part of having a massive change in the club. I felt always as a player that you want to make the Emirates a fortress, but to build that connection again the players need to really buy into that we want to go that way, and the fans will follow for sure.

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Finally, tell us about Mesut Özil – what’s he like and why his Arsenal career has been so tumultuous? First of all he loves playing football. It doesn’t come across so often. He is a genius in terms of what he can produce. Once he gets the ball, he’s rested, he thinks he plays in the park, he can deliver that ball that no one else can deliver. He has got that magical sense.

He wants to be OK with everyone. He is not the kind of guy who approaches people and says: ‘You need to do this, that and that.’ He’s a different character and sometimes I struggled with that. When I approached him and said: ‘This is not what we do here,’ I thought that sticks with us longer. For him it’s: ‘No, that’s OK, I accept that, we move forward.’ I was really pissed [off] for days and weeks. But he relaxes in those moments. I know how to take him and how to try to pinch him when needed. But, ultimately, it has to come from him if he wants to go to the next level. But he can deliver. You have seen it.

Per Mertesacker’s autobiography, Big Friendly German, is available in all good bookshops and signed copies available at www.decoubertin.co.uk/BFG. RRP £20.