Erling Haaland has been urged to stay at Borussia Dortmund amid growing speculation linking him with Liverpool and Manchester United.
The 20-year-old striker has become one of the hottest properties in world football with his performances - and goals - for the Bundesliga side.
Along with Liverpool and United, Manchester City, Chelsea, Real Madrid and Juventus have also been linked with the Norwegian international.
But Dortmund chief executive Hans-Joachim Watzke thinks it is too early for Haaland to be looking for a transfer - and called on him to follow the example of Robert Lewandowski.
Poland striker Lewandowski spent four years at Dortmund before signing for Bayern Munich in 2014.
Asked about the prospect of Haaland moving on in the summer transfer window, Watzke told Kicker : "I don't think that will happen.
"Erling and his advisor Mino Raiola know what they have in us.
"I can only advise him to do things like Robert Lewandowski."
Haaland has only been at Dortmund for a year after being snapped up from RB Salzburg last January.
And Watzke believes the youngster still has plenty to learn.
"Haaland gave himself the time to mature into an absolute world-class player in Dortmund," he added. "You won't be able to do that in a year.
"Because it is clear that if Erling should leave us at some point, then he will only go to an even bigger club, and so many are not considered.
"If you join a club like - just for an example - Real Madrid, you have to be world class."
The Mirror reports that Haaland has a release clause in his contract but that does not come into effect until 2022, making a transfer this summer more expensive.
His agent Raiola has close links with Juventus but Haaland has played down reports he could be on his way to Italy.
"Have I been close to Juventus? That's what they say, but I've never said it," Haaland told Tuttosport.
"I've been at Borussia Dortmund for a year here, I'm fine here and I'm happy."
