The jump from youth football to professional football is always a very difficult one. Despite his successes for Bayern Munich during the 2025/26 season to date, the same is true for Lennart Karl. Lest we forget, his only minutes in professional football before this season were his 45 minutes in the Club World Cup. He has made the transition look easy with many, many phenomenal performances this season.

But Karl is still a slight, 5’5″ player. Asked by Kicker what the biggest adjustment going from youth to pro football has been, there was only going to be one answer:

“The biggest differences are clearly the physicality and intensity; the training is much more strenuous than in youth football,” Karl said, as captured by @iMiaSanMia. “I can’t compare dribbling against a 17-year-old to dribbling against [Bayern teammate] Dayot Upamecano.”

Upamecano has been mentioned several times by other Bayern players as a fearsome opponent to dribble against. The French center back is a very tough competitor and extremely tough to overcome in a footballing duel. But when Karl’s dribbles do come off against him, how does Upamecano react?

“If something like that happens, I do get a reaction, but we joke about it again in the dressing room. Then it’s all good.”

Part of being a professional footballer is being treated like one. Despite only recently turning 18, Karl is being treated like a fully grown adult by teammates a decade older than him, as Upamecano is. Perhaps that is another big difference between youth and professional football.