The former Valencia and Getafe forward has played second fiddle to Lionel Messi and Luis Suarez over the course of his two campaigns to date at the Camp Nou, and is seeking a new challenge away from the club.
The 24-year-old, who made 13 appearances for Spain between 2014 and 2016, has been told by boss Ernesto Valverde that he does not feature in his plans for the new season.
The 22-year-old is one of European’s most promising young players, but he will not come cheap if leading sides decide to make a move for the German international.
Dortmund are keen to keep hold of the youngster but could be resigned to losing him if Real Madrid or PSG put their full weight behind a transfer bid before the end of the transfer window on August 31.
Advanced talks have opened up between the clubs on a move that will also include a right to buy. The 25-year-old travelled to Crystal Palace for Monday night’s Premier League game, but an agreement is expected to be concluded within 24 hours.
This will see Belgium’s Simon Mignolet remain as No2 to Brazil shot stopper Alisson.
Karius made a pair of wretched mistakes in May’s Champions League final defeat to Real Madrid. Manager Jurgen Klopp put that display down to a concussion.
But these errors continued in pre-season, expediting the then world-record pursuit of Alisson from Roma.