That was the claim by Samir Nasri, who was shipped off by the now Manchester City boss on loan to Sevilla for allegedly being overweight.
Nasri, who is now flourishing in Spain, revealed just how far Guardiola goes to get his players in peak condition for a match.
“He tells his players that if they want to have sex, keep it before midnight because you need a good night’s sleep,” the City outcast told French television channel L’Equipe.
“He claims he said it to Messi and that after that he didn’t get injured anymore,” the former France international said.
“(Robert) Lewandowski was on the bench (at Bayern) and he was made to understand too.”