Jason Smyth missed out on a place in the World Championships 100m semi-finals after finishing fifth in his heat on Saturday in Daegu.
The double Beijing Paralympic champion from Eglinton clocked 10.57 seconds, well short of his personal best time of 10.22.
However, times in the heats were slower because of a stiff head-wind.
American sprinter Walter Dix won in 10.25 while Harry Aikenes-Aryeetey and Keston Bledman also made the semis.
Smyth needed to produce the performance of his life to make Sunday's semi-finals.
The 24-year-old's PB of 10.22 was set in May in Florida and is only .04secs off the Olympic Games standard.
The Irish athlete's times before the World Championships were well down on his personal best but Smyth said that he was feeling his strongest in several months after his arrival in South Korea.
Like South African Oscar Pistorious, Smyth is hoping to achieve a piece of athletics history next year by competing at both the London Olympics and Paralympics.