The AIK Solna is star is highly rated and two big clubs have been reportedly fighting for him. However, it seems like the youngster has already taken his decision.
His agent Dickson Etuhu has posted a picture on Instagram which could confirm the transfer to the Bundesliga:
Scheinbar alles eingetütet. Alexander #Isak unterschreibt beim #BVB. Dickson Etuhu veröffentlichte bei @instagram dieses Foto. pic.twitter.com/fIeYNprHeu
— Moritz Leihkamm (@kopfballer) 23 de enero de 2017
The picture shows the youngster signing a paper and sitting next to Michael Zorc, Dortmund's sportingg director. The club hasn't confirmed the rumours yet but maybe we have to wait a few more hours until they announce their new signing.
Click here to read more about Isak.