Haaland joins some of the greatest to score a treble on debut.
Erling Haaland is the first Bundesliga player to score a hat-trick on debut since another famous Dortmund number 9.
The wait is on as BVB prepares to unveil its newest rising star.
Haaland hasn't joined BVB as a speculation buy.
Hummels is forcing a German re-think.