Perez made the comments during Asier Illarramendi's presentation.
"We continue to work and look for the spectacular football that Carlo Ancelotti wants," Perez told reporters. "We have an exceptional squad and a team of immense quality, but we are convinced we must keep working to continue being the best club in history.
"Today, a fantastic player arrives at Real Madrid, one who has become one of the great pearls of our game. Asier has been hailed as one of the best players of the [Spain] Under-21 side and he shares the dressing room with many players who are part of that team."