The 52-year-old was full of praise his fellow Portuguese and Manchester United boss Jose Mourinho ahead of their first ever match against each other as managers.
Carvalhal said: “He (Jose Mourinho) is our king of football, he is the best manager ever for Porto. He opened the doors for the new generation of managers to go abroad. He opened the ideas of the world on Portuguese coaches.
“He’s a fighter – what I mean is he’s very good at mind games.
“The way he acts, he likes the theatre of it, and he usually wins all these battles. I am completely different, I prefer to be out of the theatre.”