Flick’s frustration boiled over as Yamal was sidelined with a pubic injury, missing key fixtures against Valencia, Newcastle, Getafe and Oviedo.
"They gave him painkillers and he played 73 and 79 minutes. And between the matches, he didn't train," the German boss said. "That's not taking care of the players. Spain has the best players and the best national team, but they haven't taken care of the players, and that's what I can say. I'm very disappointed."
Despite the youngsters absence, Barca maintained form with four straight wins, but the long-term fitness of their young star remains a major concern for both club and country.