Courtois recalls that when he arrived at the club, his rival for the No.1 shirt was Navas, a good friend of club captain Sergio Ramos.
"I knew him a bit before, from a holiday in Ibiza. He's good friends with Navas, so it wasn't easy for him at first," Courtois said in an interview with Sporza.
"But he welcomed me well, we never had problems."
In those early days Zinedine Zidane would often rotate between the two keepers, a situation that wasn't easy for the Belgian, but he says that he has a good relationship with the head coach.
"[Zidane] likes to rotate but that has nothing to do with my relationship with him. It might have been a little distant at first, but that was also because I didn't have a history with him like the others did," Courtois explained.
"He himself realised that and in the summer of 2019, we had a good conversation. Since then, our relationship has grown and now it is very good.
"He is a calm person, a good motivator, but also straightforward. He says things like they are."