It didn’t look good when he went down. The way the knee buckles to the outside, the wincing facial pain and immediate arm in the air should concern everyone.
My best for a speedy recovery. He is young and probably about as flexible as could be. Hopefully, it is a tweak and a bit of fluid on the knee. Either way, he’s going to need a good rehab period and another pre season, so I’d expect Bayern to wave this season off and be back next season with a £60M bid or a word in his ear for a mega-payday and just wait until Summer 2021. He is young enough to wait for, especially given their layouts already this summer.