The 24-year-old Germany international, who joined Barcelona from Borussia Dortmund on a five-year contract until June 2031, is expected to make his unofficial debut in Friday's pre-season friendly against Birmingham City.

Barcelona completed the transfer on July 23 for an initial fee of 22 million euros, with a further seven million euros in performance-related bonuses. Borussia Dortmund also negotiated a sell-on clause as part of the deal.

Speaking to Mundo Deportivo, Adeyemi revealed Flick's phone call was all it took for him to make up his mind.

"Convince is the wrong word. He simply called me and asked if I wanted to go. I told him of course, because it's the biggest club in the world and these opportunities only come once.

"He didn't have to convince me. I've trusted him for a long time, and I have a lot of respect for him."

Adeyemi previously worked with Flick during his time with the German national team and believes that relationship can help him settle quickly at Camp Nou.

"I hope he sees things in me that I can contribute to the team on the field. He knows me very well from the national team and we're very close."

The forward admitted Barcelona had shown interest in him before, but this was the first time a move became a reality.

"There were some initial contacts, but nothing concrete."

Adeyemi also knows what it is like to face Barcelona after meeting them in the Champions League with Borussia Dortmund in 2025.

"It's one of the best matches you can play. You're up against a great team, a great club, and you're always motivated when you play against the best. Those two matches were really tough, but we enjoyed them."

Despite joining a squad that already includes teenage star Lamine Yamal, Adeyemi made it clear he is ready to compete for his place.

"No. I'm not afraid of any player. I know that if I give my best, I'll have a chance to play."

The winger also hopes strong performances for Barcelona will earn him a return to the Germany squad.

"Ultimately I have to prove it on the field. Only I can decide whether I return to the national team or not. I'm convinced that if I play well, I'll be there."

Adeyemi believes his pace is only one part of his game and says his versatility will be a valuable asset for Flick.

"I have speed, of course, but I also have other things to contribute to the game. I'm good in one-on-one situations, I can play on the wing or as a centre forward. I think I'm versatile and that's what makes me different."

Looking ahead to the new season, Adeyemi has one major target in mind.

"Of course, my dream is to win the Champions League. I almost did, but unfortunately we lost, and it's my dream. That's what I work for every day."

FC Barcelona will officially start their 2026-27 La Liga campaign away against Elche CF on Sunday, 23 August.

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