Brad Hamilton was the first Jamaican to dive into action at the 13th FINA Swimming World Championships being held in Rome. In the 50m Butterfly sprint event he smashed the Jamaican National Record of 25.90 seconds, swimming 25.68. Swimming in lane zero, Hamilton clearly had the fastest start, a reaction time of .64 but Romans Miloslavskis (LAT) swimming in lane five closed the gap quickly and eased away to touch first in 24.05. Hamilton's 25.68 was enough for a comfortable joint second with Suriname's Marceliano Richards in the heat and 102nd overall. He was 2.78 seconds behind the Championship Record leading time of 22.90 set by Ronald Schoeman (South Africa) and Rafael Munoz (Spain). Their times erased .06 seconds off the Championship Record set by Schoeman four years ago in Montreal.

Two other Championship records fell in the preliminary heats, as Sweden's Sarah Sjostrom swam a very fast 56.76 in the Women's 100m Butterfly to erase Lisbeth Trickett's (Australia) record of 57.15.

In the women's 200m individual medley, American Ariana Kukors surprised world record holder Stephanie Rice, to claim the fastest time and a championship record time of 2:08.53.

The previous championship record of 2:10.13 was held by fellow American Katie Hoff.

Kendese Nangle and Jonathan Wong will swim today in the 100m backstroke and 200m freestyle respectively.

Ten lanes are being used for the preliminary heats but only eight will be used in the semi-finals and finals.