A row is brewing over who was responsible for the blunder which cost Jessica Ennis a confidence-boosting personal best in the 100 metres hurdles.
Race officials at the Powerade Great CityGames in Manchester only set up nine hurdles rather than the regulation 10, meaning Ennis' stunning time of 12.75 seconds on Sunday was scrapped from the record books.
Event organisers Nova International pointed the finger at UK Athletics, but it is understood UKA did not select the officials for the event.
Ennis, gearing up for her first heptathlon of the Olympic year in Gotzis this weekend, described the error as a "massive, massive mess-up".
The 26-year-old went on to say she felt "let down", "annoyed" and "disappointed".
It was not until about 30 minutes after the race that the mistake was officially confirmed.
A Nova spokesman said: "We can confirm that due to human error only nine sets of hurdles rather than the required 10 were put out on the track for the women's 100 metres hurdles event.
"We employ leading UKA officials to manage this vital element of the event on our behalf, and we will of course be investigating this unfortunate occurrence with them."