Speaking before Barca’s clash with Oviedo, Flick admitted the blow hurts the team but insisted the diagnosis gives clarity.
"When you receive news like this, you think it’s bad news, but for him personally, it’s good news," he said. "Now we know what to do. He’s 21 years old and has a very long career ahead of him. We have to think about this, to get him 100 percent fit and stay strong.
"He has a huge heart, he's very emotional, I wouldn't say he'd die for this club, but he lives for it. It's not easy for the team because he brings a lot of quality. We'll all help him get back to his best."