Arsenal legend Martin Keown feels Manchester United youngster Phil Jones faces a massive test against Spain.
Keown explained in his column for the Daily Mail: "It's a friendly so this is the type of game to experiment, but it would still be a rather big call by the England manager.
"Because Jones has a lot of energy, people say that he would be a good fit for midfield. He's played there for Blackburn and Manchester United, but whether he'll be sharp enough for Spain is another matter. If he can do it against them he can do it against anyone, but it would be asking a lot of him.
"Although it's clear we have an outstanding talent on our hands, he could be exposed in this position. When you're playing for England you want to play in a familiar position and his best place will eventually be central defence.
"Jones still hasn't cracked everything defensively, mind you. He's got things to learn. He has to pick and choose when he goes forward - to meet the needs of his team before he meets his own. He's well equipped to go to the very highest level, but he needs to strike the right balance in his game."