RIO DE JANEIRO • Five times a world champion but without a single medal from three previous Olympics, Hungary's Katinka Hosszu finally struck gold on Saturday, demolishing the 400m individual medley world record along the way.

The "Iron Lady" set a mind-boggling pace as she put Ye Shiwen's London 2012 mark through the wringer in Rio.

Having threatened to break that mark in the heats, the 27-year-old went a gaping 5.25sec under record pace entering the final freestyle leg with the crowd roaring her on. Her finishing time of 4min 26.36sec sliced 2.07sec off the record.

"Honestly I did not even see her. She was so far ahead," American Maya DiRado, the runner-up, said.

Hosszu was the overwhelming favourite in 2012 but managed only fourth. She was determined that would not happen again.

"I've been chasing that world record for quite some time now," she said, adding she felt she could go even faster. "It's been over seven years I've been thinking about it.

"Honestly, I didn't think I could go this much faster but it was just unbelievable that I have been able to break it by this much."

With four more races to come - the 200m individual medley, the 200m butterfly, and the 100m and 200m backstroke - Hosszu promised to have fun to make up for the misery of London.

She said. "In 2012, after graduating college and basically turning pro, I felt like London was my time. I felt a lot of pressure and was super-nervous before the final."

After the London Games, Hosszu's then-boyfriend Shane Tusup became her coach, before they got married.

"I had a lot of fun," she said. "I have been training through the whole four years. I didn't take off more than a day ... and it worked."

REUTERS, AGENCE FRANCE-PRESSE