Atletico Madrid midfielder Saul Niguez has admitted that it would be "almost impossible" to join his side's near neighbours Real Madrid.
The Spain international has been linked with a move across the city in the past, while reigning La Liga champions Barcelona are also understood to have shown an interest.
Ahead of Saturday evening's Madrid derby at the Bernabeu, however, Saul has reiterated that he has never seriously considered swapping Atletico for Real due to the rivalry between the clubs.
"Joining Real Madrid would for me be unthinkable... it would be very, very difficult, almost impossible," Saul told Cadena Ser. "On Saturday there is no favourite, the only thing we can know for sure is that it will be a beautiful game.
"We are a team who are growing and its natural that we are exposed to criticism because of this profile, but we do not want to be compared to Madrid or Barcelona.
"We are working to reach this level of course, and I believe at least six Atletico players would be starters in Madrid's team, but we need to remain level-headed."
Saul has started five of Atletico's league games this term and was on the scoresheet in their 4-2 UEFA Super Cup win over Real Madrid last month.
