(CNN) -- David Rudisha underlined his domination in the men's 800m by taking his first global gold, but Russia's Yelena Isinbayeva failed in her bid to regain her pole vault title at the world championships in Daegu, South Korea. Tuesday.
Rudisha, who set two world records last year and won the IAAF world athlete of the year crown, led from start to finish to win from Abubaker Kaki, who claimed Sudan's first ever medal at this level.
His time was, by his standards, a modest one minute 43.91 seconds, nearly three seconds slower than his world record, but for the 22-year-old the victory was all that mattered.
"I controlled the race from the start, that was my plan," he told AFP.
"I did not want to make a mistake. And I also knew that I was in good shape. Nevertheless, I spared my energy until the last 150m."
Isinbayeva once dominated her discipline in the manner of Rudisha, but after failing to record a height at the 2009 Berlin world championships, her form has fallen away.
Nonetheless, she was still favored to win back her crown and after coming in at 4.65m looked in good shape with an easy clearance.
However, at her next height of 4.75m she bumped the bar and chose to move it up to 4.80m for her next two attempts, both unsuccessful.
It left her back in sixth place with Brazil's Fabiana Murer winning with a best of 4.85m against Isinbayeva's world record of 5.06m.
"I'm disappointed but I'm now focusing on next year's Olympic Games," said Isinbayeva, who will be defending her crown in London.
The other highlight of the evening in South Korea was the men's 400m where Grenada teenager Kirani James edged past Olympic champion LaShawn Merritt of the United States in the closing strides.
Merritt was returning to action after a doping ban while 18-year-old James was winning his country's first medal of any type at the world championships.
There was a shock in the women's heptathlon where defending champion Jessica Ennis of Britain lost out to Russian Tatyana Chernova for gold.
The turning point was the sixth event, the javelin, where Chernova threw an impressive 52.96m against a dismal 39.95m for Ennis, who is set to be the main hope for home gold in the track and field at next year's London Olympics.
It left Chernova with an insurmountable lead for the final event, the 800m, and she finished a few strides behind Ennis to seal her triumph.
In other medal action Tuesday, Russia's Yuliya Zaripova led from the gun to win the women's 3000m steeplechase and Germany's Robert Harting took the men's discus.