Sanches moved to south Wales last summer and linked up with then-manager Paul Clement, who he had previously worked with at Bayern.
The 20-year-old finished the campaign having made just 15 appearances in all competitions, failing to register a single assist or goal.
Bayern originally signed the player in the summer of 2016 for a transfer fee of £27.5m, after his astonishing performances when helping his country win the European Championship that summer.
Despite being an integral part of Portugal's Euro-winning squad, Sanches' poor display in south Wales has forced him out of Portugal's setup this time round, as he is left out of their World Cup squad.
It remains unclear whether or not the Golden Boy winner of 2016 will have a future at Bayern, however, it is almost a certainty that whoever takes over the helm at Bayern will not allow him to return to the Premier League after such a torrid year.