Schalke sporting director Christian Heidel believes the Premier League works in a "completely different market" compared to the rest of the clubs in Europe.
Heidel, appointed as successor to Horst Heldt ahead of the 2016-17 campaign, dealt with Manchester City earlier in the transfer window as Pep Guardiola's side acquired the services of promising forward Leroy Sane.
The Germany international moved to the Etihad Stadium for a fee reported to be in the region of €43million and Heidel believes Premier League clubs' spending power means they are operating on a different plane to the majority of the continent.
Heidel revealed that City's finances meant the two-time Premier League champions eventually made an offer that Schalke simply could not turn down.
"The [Sane] talks were not that different to any other transfer with a German club," he told kicker.tv. "However, the transfer fees are some other categories, luckily for Schalke.
"You start very, very low, because even the English teams know that the low prices are huge sums in Germany. So that was above €30million and we made clear that Sane would not leave for this fee, because even we know how the English market works.
"You cannot confuse it with the market in Germany. To me, those two are completely different markets.
"Every executive of the Bundesliga knows exactly that there will be different prices when there is an English club on the line. The problem is, that you can get really confused when you are in talks with a non-Premier League club, because we all have those English fees in mind.
"With Leroy Sane it took like two or three weeks, then we agreed on a fee, which was so huge, that at Schalke we only could say 'we just cannot deny [this offer] anymore'.
"We do have an economical responsibility to the club. With a certain fee, without confirming the €50million, we reached a point, where we just had to say yes."
