Pep Clotet expects Birmingham City to receive big money for Jude Bellingham but denied a deal with Borussia Dortmund has already been agreed.
It was reported on Friday that Dortmund have beaten off competition from the likes of Manchester United to sign the 17-year-old midfielder on a five-year deal.
Championship side Birmingham are said to be set to be paid at least £20 million ($25m) for the England youth international.
Blues head coach Clotet stressed that an agreement has not been reached, but suggested it was only a matter of time before the club cash in on the teenager.
"I have not looked into the situation at all as I am only allowed to comment on things that are not speculation," said Clotet, who will leave his role at the end of the season.
"It is up to the club and the player to decide, basically for the club to decide what to do with their assets. I am just hoping that the value, according to what he has achieved and his future potential, is rich.
"That's what I hope because he is one of the youngest players who has played so many games in the Championship for his age, on the quality of his play, in very different positions.
"He has massive future value. Of course I am expecting that possibly he will be the most valuable player I have ever developed - and I have developed a lot.
"I am expecting it to be a really good bond financially for the club but of course that is a side of the business that is not my side.
"There is no update, I know there has been a lot of speculation lately – but there is nothing.
"We are focused, Jude is our player, he is very determined to play with us tomorrow [at Fulham on Saturday] and as far as I am aware and what I see it just shows how good professionally he is.
"He just blocks everything around that and is focusing a lot on his performances and playing tomorrow. At the moment there is nothing concrete."