"He's a good player, in fact, an excellent player," Fergie is quoted in the News of the World.
"It was difficult to let him go to Villarreal. It was based on the fact that he wanted first-team football and we couldn't guarantee him that.
"When they offered the money they did for him and we got the buy-back clause, it became attractive to us.
"We'd consider buying him back. We will keep our options open."