Australia's Patrick Johnson has been knocked out in the second round of the 100m at the world athletics championships amid some of the most extraordinary scenes ever witnessed at a major meeting.

American Jon Drummond held the race up by close to an hour when he refused to leave the track after he and Jamaican Asafa Powell were disqualified under the International Association of Athletics Federation's (IAAF) contentious new false start rule which was introduced at the start of this year.

Any athlete who breaks after a first false start is disqualified under the new rules, regardless of whether they broke in the first place.

Drummond refused to accept the technology which showed he had reacted too quickly to the gun and lay on the track repeatedly protesting to officials "I did not move".

He eventually relented and walked off the track with a quivering bottom lip.

But 80m down the straight, he pulled his suit back on and stormed back to take his place on the blocks, shaking hands with his opponents and calling on the support of the 50,000 crowd which whistled and jeered.

Officials took the athletes off the track and ran the remaining two races while Johnson and his opponents tried to remain focused and warm in the outfield.

Once the race was finally run with six starters and Drummond inconsolable in the warm-up area, Johnson was the only one not to qualify for the semis.

Johnson, the fastest man in the world this year with 9.93secs in May, finished last in 10.27.

He won his first round heat in 10.29 and said the delay affected his second round race.

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