Ian Thorpe remained on course to match his record six gold medals at the last world championships when he led Australia to their third straight 4x200m world relay gold in Spain.

It was also the third gold medal in Spain and 11th overall for the 20-year-old after the Olympic and two-time defending champions timed 7:08.58 to push the United States into second spot in 7:10.26 with Germany taking the bronze in 7:14.02.

Thorpe's dream of going one better than last time came unstuck early in the championships when the Australians lost their 4x100m freestyle title.

But the 20-year-old went on to successfully defend his 200m and 400m freestyle titles and kept his bid to win the 100m freestyle for the first time on course by achieving his best time ever 48.71 in the semi-finals.

He had the third fastest time going into Thursday's final behind reigning Olympic champion Pieter van den Hoogenband of the Netherlands and two-time Olympic titleholder Alexander Popov of Russia.

Earlier James Gibson gave Britain their first individual gold medal in almost 30 years when he claimed the men's 50m breaststroke title.

The 23-year-old Commonwealth champion clocked 27.56sec to come in ahead of defending champion and world record holder Oleg Lisogor of the Ukraine, who timed 27.74, with bronze going to Mihaly Flaskay of Hungary in 27.79.

Gibson, winner of the 100m breaststroke bronze earlier in the week, gave Britain their first individual world title since David Wilkie completed a breaststroke double in 1975.

"I've been working for this for four years," said Gibson. "I had a good start, felt very relaxed, very chilled out."

Defending champion Michael Phelps of the United States held his 200m butterfly title.

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