Juventus has had a €4.5 million bid for Botafogo defender Doria rejected, with the Brazilian club increasing their asking price for the in-demand youngster.
The Serie A champions made an offer for Doria last week, but Botafogo president Mauricio Assumpcao believes the 18-year-old is undervalued and the club insists they will not release him unless a better deal is reached.
"For €4.5m, he won't leave. We've already said no to that," Assumpcao told Radio Globo. "But I don't know, the transfer market is crazy. There are players out there being sold for €100m."
Doria is highly rated in Brazil, but he is not concerned about the pressure of attracting European clubs, telling reporters before his 18th birthday on Thursday that he has the same ambition as senior players at Botafogo.
"Do not look at me differently from the others because I'm 17," he said. "They could treat me differently because of it but if I'm here it is to be treated the same way as the more experienced players.
"We are all in search for victories as a group. In football, you will not always be able to stop all strikers. We always want to defend well and to not let the goals in. You stay concentrated all the time."