It would definitely be good for the club to keep him in the team. He brings plenty of quality and development potential. Since Fernandez wasn’t fully fit at the start of his time at the club, I believe he can become an even more important factor next season than he has been so far.
At Bayern, however, they also know his potential, and it’s not for nothing that they extended his contract. Without his injuries (probably the only negative point), Nuremberg would probably never have had the chance of a loan.
I assume that the loan will simply be extended for another year. If it is a transfer, there will certainly be a buyback clause.
