Roberto Martínez admits Ross Barkley is a player who generates extremes of opinion but claims Everton is the only place where he is treated with balance.

Barkley has been criticised for having an ordinary season with his club but the 21-year-old was praised for two positive substitute appearances with England in the past week. Martínez, the Everton manager, claims that highlights perfectly the way Barkley has been treated since his breakthrough season last term, when he was a revelation.

“I think Ross is a young man who is used to having to deal with extremes,” he said. “When he plays well he is probably the best footballer that England could have and when he has a bad game it is the end of the world. It doesn’t surprise me he made a very good impact when he came on in both games for England.

“We are well-balanced around Ross. We know who he is and how good he is through good moments, through bad moments and we don’t get carried away when the extreme surroundings affect comments about his performances. We are very much level-headed in that respect. We know how important he is for us and for the future of Everton.”

Martínez praised the way Barkley has coped during a testing season, when he has had to adapt to playing in different positions after excelling in a role behind the striker previously.

“Ross has achieved an incredible level of maturity this season,” said the Spaniard. “He had to go through a period of strong difficulty the same way we have as a team and he has learned a lot. He will benefit a lot in the future after this difficult season. Remember this is his second full season in an important role in the first-team squad – that is a short period to see a player getting through experiences.

“What I enjoy from Ross is he enjoys the responsibility and enjoys taking control of the big moments in games and he has an incredible technical ability which, with the physicality he has … you don’t see many players in world football have those abilities. We are really enjoying seeing Ross growing.”

In an interview earlier this week, Barkley said he viewed himself as a striker but Martínez said that was probably a little too advanced for the youngster.

“At the moment his most effective role has been as a No10 just playing off the striker,” said the Everton manager. “Ross, as he gets games under his belt, could play in different positions with the attributes he has as a player. He is not a player who has to play in one position to have an impact in the game and that is something I see as a real strength.”