Andre De Grasse, who was seen as a possible successor to Usain Bolt, after his three medals in the Rio Olympics five years ago.
But the now 26-year-old Canadian has had to keep waiting for his championship gold.
Oviss final
He was one of the gold candidates in the 100-meter race this week, but took "only" bronze.
But today it was finally time for De Grasse to shine.
The previously uncertain 200-meter final was even for a long time, but in the race it was Andre De Grasse who was the strongest.
He finished in the cannon time of 19.62, six hundredths ahead of the American Kenneth Bednarek, and another six before Bednarek's compatriot Noah Lyles.
Both Americans were ahead of him, but De Grasse's last part of the race was superb.
Waved to the kids
De Grasse was jubilantly happy after the victory, and exclaimed a few minutes later, lying on the American flag: "Oh, wow!".
After waving and greeting his children on a TV screen on the track, it became even more emotional for him.
- My God, I did it!
I can not understand it.
I won, he said with a giant smile on his face.