The Sweden international forward moves to Spain after lighting up the Eredivisie during a loan spell with Willem II in 2018-19
Alexander Isak has completed a €10 million (£8.9m/$11.3m) move from Borussia Dortmund to Real Sociedad as he heads to La Liga following a rampant loan spell with Willem II.
Isak was unveiled by the Spanish club on Wednesday as he signed a five-year deal that will keep him with the club through till June 2024.
The 19-year-old Sweden international departs Dortmund after three seasons having made just 13 appearances for the club before heading to the Eredivisie on loan this past January.