The debate over who should be considered the world's swimming king was settled in just 45 minutes at the Barcelona world championships.

And it isn't Ian Thorpe.

American swimming prodigy Michael Phelps became the first swimmer in history to set world records in different events on the sixth day of competition in Spain, wiping out both the 100m butterfly and 200m individual medley (IM) times.

Not even Thorpe has done what Phelps did in less than an hour at the Palau Sant Jordi pool.

He set a new world standard of 51.47s in the 100m butterfly semi-finals before swamping the 200 IM field with his fourth world record in Barcelona.

Phelps hacked almost 1.5s off his previous world standard to win the medley in 1m56.04s.

Leading into the titles, the race was touted as the most anticipated of the championships with Thorpe and Phelps meeting in an individual event for the only time in Barcelona.

In the end, there was no contest.

Thorpe took silver in a Commonwealth record 1:59.66, beating Italian Olympic champion Massi Rosolino but the 20-year-old Australian was still 3.62s off Phelps's feat.

"To come here to the world championships and come second and be beaten by three seconds, it doesn't really concern me," Thorpe said later.

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