Sarah Lavin has missed out on a place in the semi-finals of the 100 metres hurdles after a seventh-place run in her heat.
Lavin finished in a time of 13.16 seconds, which equalled her second-best ever run.
The Limerick runner was trailing throughout in a strong race. The first four progressed to the semi-finals, with USA's Kendra Harrison winning the heat in 12.74 seconds.
"I never got going," she told RTÉ Sport afterwards, despite acknowledging it was her second fastest time ever.
"I was really targeting a 12.9 today and, sure enough, that would have got me through," she admitted.
"I was running someone else's race for the whole thing. You come here and you want to run your best time. I’m capable of being in a semi-final. I don’t think I’m capable of being in a final right now," added Lavin, who insisted she would learn from the experience on a sultry morning in Tokyo.
"I never got out and hurdles is a rhythm. That being said, I wasn’t here five years ago and I’ll be here in three years, hopefully. Obviously I want to go further than the heats."
Her first Olympics, the 27-year-old said she would not be ablle to savour the experiience for some time, due to her disappointment with not progressing to a semi-final.
"Come September/October I’ll take it in, for now it’s just, to be honest, overwhelming disappointment because I know, my coach knows... It’s easy to say 'coulda, shoulda’ but you need to do it. I will definitely learn a lot from this. That’s so cliché!"
