Villarreal will allow midfielder Marcos Senna to join Manchester United - if the clubs can agree on a fee.
Senna has been in Spain at Villarreal since 2002
"If the offer is good for everyone, the club would allow Marcos to leave," Villarreal's general manager Jose Manuel Llaneza told Mundo Deportivo.
Red Devils boss Sir Alex Ferguson has admitted he is interested in signing the Spanish international as he looks for a new midfield balance.
The Brazilian-born 30-year-old is likely to cost in the region of £4m.
Ferguson has previously said: "There is interest in Senna but there is interest in other players as well.
"We are trying to find different combinations in midfield."
Ferguson has already landed England international Michael Carrick in an £18.6m deal, although the former Tottenham man will now miss the start of the season with a foot injury.
Villarreal coach Manuel Pellegrini appeared resigned to losing Senna to United earlier in the summer.
I'm very sure if Marcos stayed he would continue to give his all for us
"I understand that this is a great opportunity for him but, for us, it is going to be a great footballing loss if he does end up going," stated Pellegrini.
"If he leaves, I'll be happy for him but I will be sad for the team. He is a player who has proved his class and I have always found it very strange that nobody came in for him sooner as he is a great player."
Senna, who has one year left on his contract and has been with Villarreal since 2002, was a member of the team that reached the last four of last season's Champions League.
The blow of any potential departure would be softened after their capture of Leandro Somoza from Club Atletico Velez of Argentina and ex-Arsenal star Robert Pires.
But Llaneza said there would be no problem for Villarreal if Senna's prospected move fell through.
"I'm very sure if Marcos stayed he would continue to give his all for us," he added.