Wigan Athletic boss Roberto Martinez is dead against his players using pills.
He has warned Roy Hodgson that England are gambling on players' futures by dishing out sleeping pills.
And the Wigan manager said dosing them up on energy tablets is just as risky - calling it "a step into the unknown".
Martinez is one of the game's most knowledgeable and well-read bosses on the value of diet and nutrition.
He said: "Footballers need to train well and to sleep well - eight hours.
"But I'm not a big lover of sleeping pills as you can't be sure of effects further down the line."