Dortmund have signed Alexander Isak despite Real Madrid's interest
Real Madrid were said to have agreed a five-year contract with Sweden sensation Isak only last week.
The Bernabeu club were thought to have secured an £8.9million deal with his side AIK to bring the 17-year-old to Spain.
But Dortmund have swooped in for the striker, dubbed the 'next Zlatan Ibrahimovic'.
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Manchester United and Chelsea were among 90 clubs that sent scouts to watch Isak in the Swedish top flight last season.
Their representatives were spotted at a clash against IFK Goteborg in October.
Isak rose to prominence when making his AIK debut last February and scored in his full Sweden debut on 12 January at the age of 17 years and 113 days.
United were thought to have eyed the striker but the emergence of Marcus Rashford appears to have put an end to their interest in landing young strikers.