Reports have Senna linked with Juventus, having piqued Claudio Ranieri's interest. And while Marcos has not spoken out about it, his agent had plenty to say: "A lot depends on the club. Senna has proven himself to be one of the best players at the European Championship, but if the two teams found an agreement he would be very willing to join the Bianconeri."
There have been times in the past where I felt Senna was past his prime. During the difficult winter months last season, Senna seemed tired, and seemed to drag the side down with him. He is 32, after all. But he has picked up his play, returning to his previous stellar form. Villarreal are truly built around their captain. If Senna were to leave, serious doubt would be created about where the leadership would come from in the squad. Presumably Javi Venta or Pires could take over a captain's role, but the loss would be tremendous.
If Senna were to leave, a move for Lucho would be much more realistic - and possibly necessary. Regardless of who it was, someone that could be a huge presence in midfield would have to come to replace Senna.