Joao Felix would be "at a higher level" if he had joined Real Madrid instead of Atletico Madrid, claims Carlos Carvalhal.
Atletico shelled out €126 million (£122m/$142m) to sign Felix from Benfica ahead of Antoine Griezmann's departure for La Liga rivals Barcelona last year.
However, the 20-year-old has only contributed six goals and three assists in 28 appearances, with ankle and hamstring injuries sidelining him for separate short spells.
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Carvalhal, who is the head coach at Primeira Liga side Rio Ave, does not think the style of football played under Diego Simeone suits Felix.