Wales manager Chris Coleman highlighted Gareth Bale's potential to earn his side a victory over England, saying the forward can "change a game in an instant."
Bale scored Wales' first in their 2-1 win over Slovakia and Coleman was asked how England boss Roy Hodgson would prepare his side to face the Real Madrid man in Lens on Thursday.
Coleman, who described Bale as "easy to coach", cast doubt on whether a plan to contain the 26-year-old would be worth Hodgson's while.
"I couldn't tell Roy Hodgson anything - he's been there and done it as a coach," he said.
"It won't be the first time England have faced a great player. Will they have a plan for Gareth? Who knows.
"The thing about great players is, you can work on a plan as much as you like but it doesn't mean it is going to work. Great players can change a game in an instant.
"I'm not sure Roy will have a special plan for Bale."
Bale's performance against Slovakia prompted questions about whether his free role in the Wales side suits him better than the wide position he is deployed in at club level.
Coleman acknowledged Bale was the focal point of his team, saying: "I'd be lying if I said we don't set up our team to get the best out of him and [Aaron] Ramsey. That's no big secret.
"When he plays for Real he's got different players around him. He has played wide for us and he's equally effective there, but his job for us is different.
"It's important that when we regain possession he is in different positions to the ones he receives it in at Madrid."
Coleman refused to be drawn on the hype surrounding the first ever clash between Wales and England at a major tournament finals.
He said: "England are an obstacle in front of us. I'm not disrespecting England when I say it's just another game for us.
"There's a bit of spice on top with it being Wales and England, but it's another opportunity for us to get what we need."
However, he warned his players not to let the occasion get the better of them, adding: "You must keep control in these games.
"Ten men against a team like England is asking for trouble. My team talk won't be aggressive. I'll make sure they're focused and calm.
"We've got to make sure that the game and the occasion doesn't get the best of us. We must go about our football, do our best, and enjoy the game."