Andre De Grasse, one of Usain Bolt's main rivals for the 100 metres, has been forced to withdraw from the World Championships due to a hamstring injury.
The Canadian won bronze in the 100m at Rio 2016, as well as 200m silver and another bronze in the 4x100m relay.
But he will not add to the two bronzes he claimed at the 2015 Worlds after confirming via a statement on social media that a hamstring tear sustained in training means he will miss this month's event in London, set to be Bolt's swansong to a glittering career.
"To my fans and my supporters, earlier this week in practice, I suffered a hamstring tear that has forced me to withdraw from the World Championships," he said.
"Injuries are a part of the sport, and the timing of this one is especially unfortunate.
"While I'm in the best shape of my life and extremely disappointed that I will not have the chance to compete for my country in London, I can't forget or be ungrateful for the successes that I've been blessed with up to this point in my career.
"Thank you to my family, friends and fans that have supported me all the way….. I'll be back stronger and faster than ever."