In an interview with Telecinco's La Mirada Crítica, Juan - who previously served as Rubiales' chief of staff before being sacked in May 2022 - branded his nephew as "authoritarian, sexist and at times racist".
He added: "My nephew is a compulsive liar. He has tremendous ambition. He is a man consumed by the desire for money, [and] luxury. He is a person obsessed with power, the eroticism of power, feeling like 'number one'. He gives you the money. He is obsessed with fancy meals, fancy trips, with sex, he needs help."