Amusan came in with a record time of 12.12 seconds, beating Kendra Harrison’s 2016 record of 12.20 by 0.8 of a second.
She went on to bag gold in the final, though her initial finishing time of 12.06 was ruled out due to strong wind speeds.
Amusan’s world record sent shockwaves through the athletics world.
In November 2016, the now-25 year old tweeted: “Unknown now but soon I will be unforgettable, I will persist until I succeed.”
“I could not believe it when I saw it on the screen after the semis. But it was just a matter of time,” Amusan told reporters Sunday.
But some expressed skepticism at the race, which saw numerous competitors run their best times ever.
“All athletes looked shocked,” the former 200 and 400 meter runner said.
“Heat 2 we were first shown winning time of 12.53. Few seconds later it shows 12.43. Rounding down by .01 is normal. .10 is not,” he said.
Johnson received swift and fierce backlash for his comments, and later returned to Twitter to clarify further, pointing out that he had predicted that Amusan would win.
“As a commentator my job is to comment. In questioning the times of 28 athletes (not 1 athlete) by wondering if the timing system malfunctioned, I was attacked, accused of racism, and of questioning the talent of an athlete I respect and predicted to win. Unacceptable. I move on,” he said.
CNN has reached out to World Athletics for comment.