Real Madrid are reportedly interested in Watford left-back Miguel Layun, who is currently on loan at Porto.
The Spanish giants are believed to be keen to find a new back-up for Marcelo and have also been linked with Wendell and Ricardo Rodriguez.
According to Tiempo Real, Madrid are keeping tabs on Layun, who joined Porto on loan with an option for the Portuguese club to buy him at the end of this season.
The full-back joined Watford from Club America in January 2015.