Great Britain's Tiffany Porter has admitted that she made "a lot of mistakes" in the women's 100m hurdles final at the World Athletics Championships in Beijing.
The 27-year-old took bronze in the event in 2013, but she failed to medal after finishing fifth in the showdown at the Bird's Nest.
"I'm very disappointed," Porter told BBC Sport. "You go out there to do your best, I tried my best, it didn't happen so I have to congratulate the ladies who medalled. I made a lot of mistakes."
Jamaica's Danielle Williams took gold in a personal-best time of 12.57s, while Germany's Cindy Roleder claimed silver and Alina Talay of Belarus earned bronze.
