Derval O'Rourke could not make it past the semi-finals of the 100 metres hurdles, despite running a season's-best at the Olympic Stadium.
The former European indoor champion clocked 12.91 seconds to finish fifth in her semi-final.
She said: "I wish it had been better. I think there is more in me. I ran my season's-best twice (including in the heats) so I have to be satisfied. I am satisfied but not happy. I feel like I am good enough to be in a final."