Harry Redknapp splashed out ?8m for Sandro last season and could use the cash to fund improvements elsewhere in the squad which is already brimming full of midfield talent.
The Brazilian, 22, made a slow start to his White Hart Lane career, featuring just eight times for the club before the turn of the year.
Wanted man: Sandro is being tracked by Villarreal
But he came to the fore as Tottenham's Champions League journey ignited and was instrumental in the north London club's stunning victory over AC Milan at the San Siro.
Villarreal owner Fernando Roig has money to spend and is looking for some marquee signings to help the club improve on their fourth place finish in La Liga last term.
The Spaniards have opened tentative talks with Sandro's agents and are poised to swoop if given the green light by Tottenham chairman Daniel Levy.
San Siro hero: Sandro was in sparkling form for Spurs in the Champions League
?Diarra set to snub United and Spurs as France international reveals he wants Real stay Tottenham consider yet another appeal over Olympic Stadium despite High Court rulingSpurs eye move for ?7m-rated Forlan as Atletico put striker up for sale All the latest Tottenham news, features and opinion ?Explore more:People: Daniel Levy, Harry Redknapp
Source: Daily Mail
Source: Daily Mail