Ennis, 26, ran 12.75 seconds in winning at the Powerade CityGames in Manchester, but embarrassed officials discovered, via a tweet from Kelly Sotherton, only nine hurdles were set out.
The Sheffield-born heptathlon star was clearly angered by the mistake but plans to be on top form again as she steps up her preparation for the Games in Götzis.
“I need to run like that in the Heptathlon, definitely,” said Ennis.
“I’m going to go into next weekend giving everything. I know I’m in good shape and I know I’m capable of the time, but I am frustrated because it’s just so annoying.
“It was important for me to get race sharp ahead of next weekend. I need to run a time like that in the hurdles and get some solid performances in and be consistent.
“What can I say? I’ve still had a good competitive race but I’ve just not got the result that I wanted.
“Maybe I’ll have to save it for next weekend. And I’ll check – I’m going to walk down the stretch and count.”
Ennis claimed two impressive scalps in the race down Manchester’s Deansgate – storming past 2008 Olympic champion Dawn Harper, and finishing well ahead of hurdles specialist Gemma Bennett.
However, the 2009 world champion cut a dejected figure when it was confirmed her personal best will not stand due to ‘human error’, but feels that her winning was going to be the only outcome.
She said: “It’s a great event but that’s a massive, massive mess up.
“I feel a little let down because it’s a great opportunity for me to come and race here, but as an athlete, you should expect things to be set up and there should be no mistakes, so I am disappointed.
“The outcome probably wouldn’t have been any different because I was coming through strong at the end.”
© Sportsbeat 2012
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