Pep, Jochim Lowe, Flick and Heynckes all had issues with him.I still don't know how this Sane "attitude problem" backstory was manufactured! It's like some posters just decided to create a Hollywood style villain "origin" story just so they can conveniently stick the bad guy tag on him.
Sane on his game was a simply outstanding footballer, he has the talents to be one of the very best, but he simply isn't and the club that paid him a fortune to "come back home" now want to get rid should tell you everything about him.