Vitor Pereira has admitted that Joao Moutinho could leave Porto this summer, amidst reports the 25-year-old is being tracked by Tottenham.
The midfielder has been earmarked as a priority for new Spurs coach Andre Villas-Boas in the event star player Luka Modric departs White Hart Lane before August 31.
And while Pereira acknowleged the importance Moutinho bears to his squad, he appeared resigned to losing the Portugal international if the English club make a move.
"I have not spoken with Villas-Boas, but it is natural that he likes Moutinho," he told reporters. "I like him, too.
"Clubs cannot just not sell. We really want him to stay, but this is football and there are release clauses.
"The only thing we can do is achieve results with what we have got."
Moutinho, who joined Porto from Sporting Lisbon in 2010 in an €11 million deal, has a €40 million release clause attached to his contract with the Portuguese champions.
He played an important role in Villas-Boas' Porto squad, which secured four titles in 2010-11, including the Europa League.