Ståhl started the competition with a long throw of 67.26.
Neither he nor anyone else hit it before the fifth round when he himself got the discus 68.65 meters away.
At the gala, they used the format where the top three get to make a decisive throw for the victory in the final round.
Slovenian Kristjan Ceh threw 65.72 meters and Ståhl had to manage to take home the victory.
He then threw exactly the same distance and because he had thrown longer before, he was declared the winner.
Third was the Austrian Lukas Weisshaidinger.