Andrea Stramaccioni has no doubts Allan will make a big impact at Everton.

Stramaccioni coached Allan at Napoli.

He told evertonfc.com: “Allan immediately impressed me because of his hardworking attitude.

“He was pushing 110 per cent in every training session.

“Sometimes too much and I calmed him down a little bit to manage his energy during the week.

“His character was always positive, whatever the circumstances, he didn't change.

“He grew up a lot in that season [2014/15], playing differently from his previous seasons in Italy.

“I moved him 15-20 metres up the field, changing his mentality to focus on recovering the ball higher – and joining our counter-attack to try to be more effective with scoring and assists.

“He made a big improvement. He was playing as a number eight, a box-to-box midfielder, adding offensive support to the team, without losing his best ability: recovering balls.

“Everyone started to talk about him after we won against Inter Milan (2-1 away in December 2014) and drew at home with champions Juventus (0-0 in February 2015), when he was man of the match with a superb performance against Paul Pogba and Andrea Pirlo."