Tiago Mendes is confident that Atletico Madrid are in good hands for years to come due to the presence of a pair of quality attackers.
25-year-old France international Griezmann, in particular, is expected to continue to flourish for Los Colchoneros after scoring 57 goals (32 last season) since arriving from Real Sociedad two years ago and midfielder Mendes has backed him to join the world's absolute elite in the not too distant future.
"Griezmann had a fantastic season," Portuguese veteran Mendes told Tribalfootball of the forward who was unable to guide Atletico to victory in the Champions League final while also missing glory at Euro2016 with his country.
"Unfortunately for us and for him he lost two finals, two big titles.
"Although I was happy that he lost the second one because it was against Portugal…(laughs)
"But he is a fantastic player. He is intelligent, he's technically great, he scores goals.
"He will be top three in the world for sure."
Regarding promising midfielder Niguez, who has been heavily linked with Manchester United in recent times, Mendes has high hopes for the 21-year-old who has been a Rojiblancos player since making his way across the Spanish capital from Real Madrid as a kid in 2008.
Mendes added: "They are already very, very good players.
"Saul Niguez. A young player with a lot of quality.
"He's strong, he can play several roles in the midfield.
"He has a big future ahead of him."