at the Union Buildings in Pretoria
Rome - South Africa's Cameron van der Burgh broke his own world record to win the 50 metres breaststroke gold medal at the world championships.
A nervous Van der Burgh won in 26.67 seconds, beating his biggest rival, Felipe da Silva of Brazil, who was second in 26.76.
This was a great achievement for the 20-year-old South African, who won bronze two years ago at the world championships in Melbourne.
It was a close race, with Da Silva just 0.09sec behind Van der Burgh and Mark Gangloff of the US third in 26.89.
"Record breaker" is definitely a name that suits Van der Burgh, who seems to break a record every time he dives into the pool.
"It is just amazing to be a world champion," he said. "I am just so happy as this is the biggest day in my life.
"You are really going to battle to wipe the smile off my face. I really hope that I will not cry on the podium like a little girl.
"Records come and go, but medals are forever."
Silva only had good words for his rival. "I am very satisfied with this (silver) medal," said the Brazilian.
"Van der Burgh is an awesome swimmer. I started the race badly, but then I was able to come back. I am very excited because this is the first medal for Brazil at a world championships since 1994.'
Van der Burgh's gold placed South Africa ninth on the medals table.
Earlier, Lyndon Ferns earned himself a spot in the 100m freestyle final, while Roland Schoeman failed to even qualify for the semifinals, finishing 23rd place in the morning heats with a time of 48.69sec.
Ferns lowered his own SA and African record from 48.00sec to 47.94 when he swam in the first leg of the 4x100 freestyle relay on the first day of these championships.
He took the mark down again when he clocked 47.79 in Wednesday's heats.
Sebastien Rousseau had to face Michael Phelps in the final of the 200m butterfly.
The multiple Olympic champion won the event easily in a new world record time of 1:51,51.
Rousseau finished in seventh place in 1:55,43, slower than his new South African and African record of 1:54,51, which he swam in the heats.
There was disappointment for Darian Townsend as he failed to qualify for the final of the 200m individual medley, finishing 11h in 1:58,50.