Mandzukic is confident that Croatia will be able to score against Pickford in Wednesday's semi-final, despite his strong performances so far.
Mandzukic and Andrej Kramaric spoke about Pickford at a press conference in Moscow, and said that Pickford's goal was breachable.
Mandzukic said: "We've seen that he is doing very well at the World Cup. He has good potential and I'm sure he has a bright future. I believe someone will find a way to surprise him."
The Croatian striker team also rejected the idea that Croatia's age and experience would give them an advantage on Wednesday.
"England was one of the favourites for me before tournament because they have a young, hungry team with no international movie stars."
Mandzukic was in the side which knocked out Tottenham in last season's Champions League, playing against Harry Kane, Dele Alli and Kieran Trippier.
They both stressed that there is a big difference between club football and international matches:
"It's difficult to compare clubs with the national team. We know every England player, respect them as a team and individuals. It's a 50/50 chance. England deserve to be here. We deserve to be here."
Croatia will have to recover from back-to-back extra-time and penalty shootout games.