Bologna still need to pay Ramirez's former club Penarol two installments of 750,000 to ensure the complete transfer of his rights.
"Everything is in place with the Uruguayans," said Bologna director of sport Carmine Longo. "I'm willing to bet on it.
"It would be crazy to sell Ramirez right now. He is the best 20-year-old in Europe. He is equal to Alexis Sanchez.
"You'll see that within two years, he will be on Sanchez's level. For this reason, we're not selling Gaston. His price will triple."
Asked to give a valuation, Ramirez's agent said: "At least 15m or 20m."