How often has Filip Kostic rushed down the left side of the Frankfurt Waldstadion and crossed the ball inwards over the past four years?

There were always inimitable moments when the spectators got up from their seats and a murmur went through the arena.

Filip Kostic could have become an eternal legend in Frankfurt, on a par with players like Yeboah, Grabowski or Hölzenbein.

But instead of playing the Champions League with Eintracht after winning the European Cup, he prefers to go to Juventus Turin, and that too because of the defeat of the century in the Supercup against Real Madrid.

Football is and will always be a business

You can't blame the player for the change: Kostic has done great things for Frankfurt, the Italian league was obviously his dream.

And yet the transfer of the Serb is an example of how little room professional football still leaves for romance.

Players who are still kissing the club's emblem today are already under contract somewhere else tomorrow.

Football, in which many people invest a lot of heart and soul, is one thing above all: a business.

This also applies to the Frankfurt location, which prides itself on the special closeness between fans and club.

The latest example of this is the expansion of the Waldstadion, where the number of standing places on the north-west curve will be increased: the capacity of the entire arena is to be 60,000 instead of the previous 51,500.

At first glance, as well as the wondrous growth in the number of members to more than 110,000, this is a positive development.

More viewers also bring more money into the coffers.

Eintracht needs the basis

But money isn't everything, especially not at Eintracht.

Because the unwavering love of their supporters is an essential part of the identity of this club.

Players come, players go, no matter what their name is Filip Kostic.

But the followers remain - and want to be understood as part of the big picture and not just as paying consumers.

It is all the more important that those responsible at Eintracht do not completely succumb to the forces of the market when it comes to success.

In the pursuit of more members, more tickets sold, shirts and sausages, it is important not to lose the true fan who comes to the stadium even when things are not going so well - and these times are known only too well in Frankfurt.

Eintracht must try to keep players like Kostic in the future.

It will be even more important not to let the gap between clubs and their base, which is growing in the Bundesliga business, get too big.