Chelsea are reportedly keen on signing up Nicolas Otamendi, according to the Superdeportes website.
The Argentine international joined Valencia last February in a £9.5m deal before being loaned out to Brazilian side Atletico Mineiro.
Otamendi has returned to Los Che this season though and is considered an important part of their project by president Amadeo Salvo.
But with Chelsea looking to add some more defensive quality to their ranks, they have once again been linked with a move.
However, insist that Valencia have no intention of letting the 26-year-old leave without a fight.