A little tension could be considered healthy in FA Cup final week but Per Mertesacker’s dedication to loosening up means his working day continues long after many of his Arsenal team-mates have left for home.

“It’s every week, I can’t miss it,” he says of the yoga session that has kept him behind at the club’s London Colney training ground. “I did it a bit before but it’s not normal there is a yoga teacher coming to a football club. I try to strengthen my body, stretch my body and there is the mental part at the end as well – to relax and calm down.”

Mertesacker holds the routine close and it is not difficult to see it has been a reassuring constant this season. The German centre-back was integral to an Arsenal defence that conceded only 11 times in its last 18 Premier League games but was at equally close quarters to most of the 25 goals shed in the first 20. He admitted in October his participation in his country’s World Cup win was affecting his focus and, with further distance, says it took almost six months to regain the kind of form required to hold his own domestically.

“In the first months, in particular, it was quite difficult to come down and to forget that feeling of being a World Cup champion,” he says. “It took nearly half a year to realise that. Most of the players [who had been involved in Brazil] got injured; I avoided that but didn’t play at my best and that was because I hadn’t experienced this feeling before. Sometimes I didn’t know how to handle the situation.

“The season started, everyone was setting new targets and you need to be really focused on that. Obviously with all the reviews and the pictures, and what you have gone through, that takes some time. To come back to a level where I know I can push on and put myself in a situation where I want to have new targets after the World Cup … it took half a year and I expected a worse season from myself, honestly. I expected something more severe.”

It was a situation second-guessed by Arsène Wenger, who sat Mertesacker down and provided past examples of differing reactions to international success. “He spoke to me because he had a few examples for me,” says Mertesacker. “It was very interesting for me how certain players coped with the situation. A few managed to deal with it and a few didn’t. I think he mentioned Vieira, who coped with it really well. He gave me kind of a challenge – ‘I want you to come back quickly and find your form quickly’ – because he knew it was going to be difficult.

“I knew maybe there would be some criticism but I didn’t get injured so I tried to prepare even more – doing more yoga, more treatment, more things like that to come to a certain level where I could compete again.”

Whereas Mertesacker feels fortunate to have stayed fit despite bypassing anything resembling a pre-season, he believes his Arsenal and Germany team-mate Mesut Özil benefited from spending three months on the sidelines between October and January with a knee problem.

“That was a good one for him,” he says. “His brain told him: ‘I’m not ready.’ I think 80% of us got an injury. A lot were out of form, out of the good performances that we were used to having. It was a kind of a trauma and it’s important to come back stronger.”

A clearer head and newly attuned body made it easier, Mertesacker says, “to think about doing something special with the FA Cup and to qualify for the Champions League directly” in the second half of the season. The journey between the peaks of Maracanã and Wembley, via months of bread and butter, has not been smooth but Mertesacker – who will continue to captain Arsenal against Aston Villa in the absence of Mikel Arteta – says the appetite is ready for the kind of display that would win a second FA Cup in successive seasons. In Arsenal’s four successful appearances at Wembley from the past 13 months, it is a quirk that their only entirely convincing performance came in August’s 3-0 Community Shield win over Manchester City.

“We’ve done well there but have not shown our best form, which is weird,” he says. “Against Championship sides, Premier League sides, Hull [in last year’s FA Cup final], it was always a tight game. You can’t compare it to a league game – it’s difficult but we’ve been through it last season and it can be advantage. Just be aware that anything can happen on the day.

“Everyone is really up for it. It’s another special occasion for us to show we are capable of winning something. But we need the right attitude to compete at that high level and we need to turn up with our best performance, maybe of the season, to grab a title again.”