American Michael Phelps claimed a record-equalling sixth gold at the World Championships in Melbourne when he stormed to the 100m butterfly title.
Phelps stayed on track for his bid for eight golds in Melbourne
Phelps beat USA team-mate Ian Crocker in 50.77 seconds - just 0.37 outside Crocker's world record of 50.40.
Venezuelan Albert Subirats took the bronze medal in 51.82.
"That's how I won the Olympic medal. You have to nail the finish," Phelps said. "I got my hand on the wall after taking the race out after 50m."
It was Phelps' biggest obstacle to overcome in Melbourne as he maintained his quest for eight golds, having lost to Crocker in the finals of the event at the last two Championships.
The 22-year-old's two final swims in the meet are in the 400m individual medley and in the 4x100m medley relay on Sunday.
Benjamin Wildman-Tobriner won the men's 50m freestyle, beating American team-mate Cullen Jones in 21.94 and Sweden's Stefan Nystrand in 21.97.
Wildman-Tobriner said: "I knew that if I could hit my start well, which I have been struggling to do, I had a chance and when I hit the water I felt it was right."
Sweden's European champion Therese Alshammar, 25, captured her first world title in five World Championship appearances when she took women's 50m butterfly gold, touching first in 25.91 secs.
Australian Danni Miatke, who won the title in Montreal two years ago, took the silver in 26.05 and Holland's Inge Dekker the bronze in 26.11.
"It's excellent. I feel terrific," Alshammar said. "I figured I wanted to go under 26 (seconds) again, but I tightened up at bit at the end as you tend to do in finals."
United States swimmer Margarat Hoelzer claimed her second gold of the Championships when upsetting Zimbabwe's World and Olympic champion Kirsty Coventry to claim the women's 200m backstroke title.
Hoelzer, 24, surged past Coventry over the final 100m to win in two minutes 07.16 seconds, the second fastest time in history for the event.
Coventry, who won a gold, silver and bronze medals at the 2004 Athens Olympics, was pushed into second in 2:07.54 while Japan's Reiko Nakamura took bronze in 2:08.54.
American Kate Ziegler won the women's 800m freestyle gold, touching first in eight minutes 18.52 seconds.
French star Laure Manaudou took silver in 8:18.80 and Hayley Peirsol, of the United States, won the bronze in 8:26.41.
Britain's Commonwealth champion David Davies qualified quickest for the final of the 1500m despite the much-heralded return of four-time winner Grant Hackett.
The Welshman swam an impressive 14:53.57, over two-and-a-half seconds faster than the next best, American Larsen Jensen who won his heat in 14:56.28.
Australia smashed the women's 4x100m medley relay world record touching first in three minutes 55.74 second, beating their own previous best of 3:56.30 set last year.
The United States took the silver in 3:58.31 and China won the bronze in 4:01.97.
The British quartet of Melanie Marshall, Kirsty Balfour, Terri Dunning and Fran Halsall finished just outside the podium places - 0.21 seconds behind China.
Liam Tancock, bronze medallist in the 100m backstroke, could be in line to add a medal from the 50m backstroke after qualifying quickest from his semi-final.
Britain's Kate Heywood made it through to the final of the 50m breaststroke as the slowest in her semi-final.
And there was also disappointment for Fran Halsall, who was eliminated from the 50m freestyle after finishing 11th in her semi-final.