Milan have already confirmed the departure of Thiago Silva this morning.
"The two players are a great loss, they are the only two players that you cannot find in the market," Nesta told the Gazzetta dello Sport.
"There is no-one suited to replace them, but perhaps with the fee received they can bring in three or four players, possibly for the future, for a prospective value."
However, the defender refused to criticise President Silvio Berlusconi for accepting the deal, just weeks on from initially rejected a 47m deal for just Silva.
"Over 26 years Berlusconi has invested his money, with everything he has helped us win some important titles, if this is a bonus then it is deserved.
"As a fan I would thank him because for a quarter of a century they have enjoyed a lot."