He added that he wanted to reserve much of his energy for the finals of the 200m freestyle, which will be held Tuesday evening. 'My big race is tonight, the 200m free is the first event.'

His compatriot Clary, who tore his swimsuit before the race, said that he had had taken 25 minutes to get ready. 'It took me 25 minutes to get into the suit.

'My coach just told me to calm down and he helped me focus on the race, so I am pretty pleased with my time under those circumstances,' he said.

But it was in the breaststroke where the most impressive performances were shown.

Ireland's Barry Murphy achieved a surprising championship record for his country in the 12th heat, when he finished in a time of 27.26, beating the previous best mark from South Africa's Cameron Van den Burgh by .12 seconds.

His record stood for just three heats though, as Australian Brenton Rickard managed to swim 0.11 seconds faster.

His time was then broken by Van den Burgh in the very next heat, with the South African coming within three hundredths of a second of breaking Felipe Franca da Silva's world record.

The Brazilian swam a 26.89 earlier this year and qualified for the semi-finals with the second-fastest time.

On Tuesday evening the finals of the men's 100m backstroke and the 200m freestyle, as well as the women's 100m backstroke and breaststroke and the 1,500m freestyle will be swum.

The championships, which started on July 17, will end Sunday.