She was only 18 and full of potential, having won a world junior title at 1,500 meters.
Johnson has won 58 consecutive races at 400 meters over the last eight years.
Tonight's winner, Collins, had never won a medal at 100 meters in a major international competition.
Kenya won the previous three world titles at 800 meters, but did not qualify a single runner for today's final.
An hour after the ceremony, he won his first national title at 200 meters, finishing 5 feet ahead in 20.50 seconds.
In 1992, she won an Olympic bronze medal at 10,000 meters.
In 2003, Collins, who is 33, won the world indoor championship at 200 meters.
Johnson has won 51 consecutive races at 400 meters.
Last year, he won the world outdoor championships at 200 and 400 meters, an unprecedented double.
She has won a gold at 100 meters and is going for four others on the track.