There seem to be many things that can get under the skin of football players and managers, but Jürgen Klopp in particular was forced to react to it.
The Liverpool coach is known for his touchline antics and with his mix of facial distortions, punches, exaggerated celebrations and the like always offers good value for money for the viewers and the television cameras.
In many ways, such joy can be almost appreciated by rival fans because it is an honest reaction that is not seen often and that reflects what many supporters feel.
In any case, the fact that he prefers to wear a tracksuit rather than a suit on the contact line has apparently become a point of discussion, but one that the German does not consider too important.
“I was a player and the next day I was the manager. In my locker room was the tracksuit of the man who had the job two days earlier. It didn't even suit me, ”said Klopp to The Guardian, quoted by the Daily Star.
"I just focused on the game. I never thought about what I look like. I know it's not too cool because we work in public, but when I came to Borussia Dortmund I thought: "Maybe I have to change".
“I was wearing jeans and a shirt for a while. But I just didn't feel comfortable. But that doesn't mean it's bad for you.
“I think the best dressed manager is Pep Guardiola. Everything he wears looks just right for him. He doesn't wear a suit, just casual things.
"Be yourself as a trainer. If you want to look great, it's wonderful. I'm just not made for it. It is important that you do what is right for you, because no matter what role model you have, you can never do the same things.
"I like it when you see the soul or the character of the coach in the team. Guardiola again: You see a team and think, "Wow, this is either Guardiola or someone who worked with him." But you can never be exactly the same.
“Dressing is part of our character. Wear what you want, but don't make it the most important thing. In the end, the game counts.
"But don't worry: you can be world champion in a suit or a tracksuit. You just have to feel good."
Given the way Klopp has looked after the Reds since he took over Brendan Rodgers in 2015, it's strange that his style of clothing was more current than his success at Anfield.