Japan's Abdul Hakim Sani Brown finished seventh in the men's 200-meter final at the world athletics championships on Thursday, losing speed in the latter half due to pain in his right thigh.
Ramil Guliyev won the eight-man race at Olympic Stadium in 20.09 seconds, claiming Turkey's first gold medal at a world meet. South Africa's Wayde van Niekerk, who won the 400 on Tuesday, finished runner up just 0.02 second behind.
Jareem Richards of Trinidad and Tobago had the same time of 20.11 as van Niekerk but settled for third as he came in one-thousandth of a second later.
Sani Brown clocked 20.63, failing to become only the second Japanese in history to win a medal in the event after Shingo Suetsugu, who won bronze at the 2003 Paris worlds.
"My leg hurt and I wasn't able to move in the last 100 meters," said Sani Brown, who at 18 years and 157 days became the youngest finalist in the event, overtaking Jamaican superstar Usain Bolt who held the previous record of 18 years and 355 days in 2005.
"I realized that it's meaningless unless you complete the race in all the rounds and end up No. 1," said the teenager, who was born to a Ghanaian father and Japanese mother. "Although I reached the final, this was a disappointing competition. It's no fun if you can't be competitive."
Koji Ito, head of development at the Japan Association of Athletics Federations, said Sani Brown is unlikely to take part in the men's 4x100-meter relay heats scheduled Saturday.
"He has leg pain, and at this point I will not use him," Ito said, adding that the sprinter has felt tightness in the back of his right thigh even before Monday's 200-meter heats and that he also consulted his coach about the matter.
"We both agreed that it's better not to push him too hard," he said.