China's Su Bingtian, the first Asian runner to break the 10-seconds barrier, said he may have run his last 100 metres after the 35-year-old sprinter struggled at a domestic meet.
The son of Guangdong farmers, Su set the Asian record of 9.83 at the 2020 Tokyo Games and became just the second Asian sprinter to reach an Olympic 100 final after Japan's Takayoshi Yoshioka at Los Angeles in 1932.
Su had hoped to retire after China's National Games in November but said he could not see himself being competitive enough after running 10.49 in the heats of last week's Grand Prix event in Guangdong province.
"The time for this race, or any other 100m sprint in May, June or July, won't differ much," he told Chinese media.
"So, (I thought before the race) if the result is good, there will be another one, but if the situation isn't ideal, it might be my last one.
"If I can't continue to bring an advantage to my team, I don't think there is any need to run on. I'd said I would run until I couldn't run any more, and I did it.
"Now I really can't run any more. I have done everything I could to the best of my ability, and I have no regrets in my career."
Su also helped China finish fourth in the 4x100 at Tokyo, with the team upgraded to bronze after Britain were disqualified for doping and stripped of their silver, and he said he still hopes to help Guangdong win the relay at the National Games.
"I will see if I can still bring some edge to the relay team in the race," said Su, adding that he would not stray far from athletics after he hangs up his spikes.
"I will, for sure, stay around the sport to give back what I've learned from decades of training and racing at the highest level to Chinese athletics," he said.