Shaftesbury Barnet 800m star Marilyn Okoro was unable to explain her shock early exit at the World Indoor Championships on Friday.

The 23-year-old flew to Valencia with realistic dreams of clinching a first individual global medal in the 800m, but instead she experienced a nightmare, crashing out in the first round.

Okoro got her tactics all wrong in a messy third heat and could only finish third in a time of 2.05:09 minutes, which left her over a second behind the final non-automatic qualifying position.

Morocco's Seltana Ait Hammou won the race in a time of 2.04:69 - over four seconds below Okoro's indoor personal best.

The Barnet runner said: "It was absolutely awful. I'll be in shock for a while having not made it through to the semi - but I don't deserve to be there having run a race like that.

"It was very scrappy and I should have concentrated on me, rather than worrying about what the other girls were doing.

"I felt so good before the race and was so ready to do something in the final - but it's not to be. I honestly don't know what went wrong."

Okoro will now set her sights on the ultimate prize - the Olympics later this summer in Beijing.

"I will try and put this down to experience and I would rather it happen here than in Beijing," she added.

Meanwhile, fellow Harrier Allan Scott also endured a frustrating time, as his 60m hurdles' medal bid came to an abrupt end, when he hit the fourth barrier of Saturday's final.

Scott was in the frame for a podium finish after impressing in the opening rounds, but, after a flying start, he crashed in to the fourth jump and lost ground, eventually recovering to finish sixth in a time of 7.65.

Scott was left wondering what might have been: "I hit the fourth hard and they all went past me, simple as that," he said.

"I felt confident and flew over the first few hurdles, so it is massively disappointing, as I felt I could win a medal. But I smashed the fourth and lost my speed.

"I can't dwell on the negatives and will get up and carry on, as Beijing is not too far away."

Meanwhile, Middlesex University student Simeon Williamson finished seventh with a time of 6.63 seconds in the final of the 60m.

Williamson was competing against Dwain Chambers, who capped his controversial comeback by claiming silver.

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