South Africa's Wayde Van Niekerk unsurprisingly defended his 400m title at the IAAF World Championships here.
The current world record holder and Olympic gold medalist finished the race with a comfortable 43.98 seconds on Tuesday night, reports Xinhua news agency.
"It is amazing to win the world title. I hope the fans enjoyed that," the South African said.
Steven Gardiner of Bahamas finished runner-up at 44.41 while Abdalelah Haroun of Qatar ranked third with seven hundredths of a second adrift.
"The first thing that I wanted to do was to reach the final, but then I had to fight for a medal," Haroun pointed out.
"I knew it was a big chance for me, and I'm very happy to have taken the opportunity."