Elaine Thompson-Herah, the two-time Olympic champion in the 100m and 200m, will miss the Paris Olympics with an Achilles injury.
The 31-year-old Jamaican, a five-time Olympic gold medallist, sustained the injury at the New York City Grand Prix on 9 June and had to be carried off the track.
Thompson-Herah - the only sprinter other than compatriot Usain Bolt to win multiple Olympic titles in both the 100m and 200m - was aiming to defend her 100m crown after choosing not to race in the Jamaica 200m trials.
She said a "small tear on my Achilles tendon" ended her chances of competing at a third Olympics.
"It’s a long road but I am willing to start over and keep working and to make full recovery and resume my track career," Thompson-Herah wrote on Instagram.
"I am hurt and devastated to be missing the Olympics this year but at the end of the day it’s sports and my health comes first."
Jamaicans have won the past four Olympic gold medals in the women's 100m.
Thompson-Herah won gold in the 100m and 200m in Rio in 2016 and defended her titles in Tokyo five years later.
She won a fifth Olympic gold in Japan as part of Jamaica's 4x100m relay team.