The former FC Porto and Portugal national team player also expressed his admiration for José Mourinho, calling him the best coach he's ever had.
Deco played under Mourinho from 2001 to 2004, winning a UEFA Champions League title, a UEFA Europa League title (formerly the UEFA Cup), two Portuguese league titles, a Portuguese Cup, and a Portuguese Super Cup.
What Deco said about Mourinho and Portugal
In a recent appearance on Romário's show, "Cara a Cara" (Face to Face), via Abola, Barcelona's sporting director, Deco, discussed potential World Cup favourites, highlighting Portugal as a strong contender.
"Spain is the most organised team right now and is among the favourites for the World Cup. You also always have to watch out for Argentina [the current World Cup champions], who have a very strong coach in Lionel Scaloni.
"After those two, I'd put Brazil, France, Portugal, and Germany, who are currently rebuilding," Deco analysed.
He also described José Mourinho as the best coach he had ever worked with, expressing his admiration for the former FC Porto and Portugal national team player.
"Because of what he meant to me, the best coach I ever had was Mourinho. He's brilliant. I worked with him for a few years, and at that time, he was a revolutionary. He did things in training that shifted our focus away from our opponents," he concluded.