Lewis Clareburt's moment of panic before gold medal race

Lewis Clareburt won his first ever world title overnight at the World Swimming Championships, yet he almost suffered a complete disaster right before the race.

Having completed his heat for the 400-metre individual medley in the morning, he went to lunch and left his swim bag outside the cafeteria. Inside were his best race suits, goggles and even his accreditation for the meet.

When he walked back out after eating, it was gone.

"I was like 'oh no, I've got my best two suits in that bag and it's not there anymore'," Clareburt said this morning after winning gold.

"They're pretty trustworthy people here [in Doha] to be honest... within half an hour they'd got it back to me."

The 24-year-old shook off the heart-in-mouth moment to go on and win the final later in the evening, his first ever world title, and New Zealand's second gold medal of the meet after Erika Fairweather claimed gold in the 400m freestyle last week.

He sat in fifth at the start of the race, moving up to third during the backstroke.

The 24-year-old then made his move in the first lap of breaststroke, moving up to second before taking the lead during the freestyle to win gold in 4.09.72s.

Clareburt yelled "yes" as he saw the result, celebrating with a pukana in the pool.

Clareburt was pleased to be back swimming at his best following what he described as a "tough couple of years" since the Commonwealth Games.

"It's been a tough couple of years for me. I think I lost a lot of confidence over the last couple of years in myself and my ability. I think being able to win and swim a pretty good time gives me more confidence moving forward towards Paris."

Clareburt moved north from Wellington to Auckland late last year, having struggled for lane access and having run-ins with local coaches. It was a big step to take given he was leaving behind long-time coach Gary Hollywood and his hometown and join the North Shore squad under the tutelage of Mitch Nairn.

"It was a huge risk to take to leave Gary and my hometown and my home setup that was working for me. But seeing results straight away is good, it's promising. But we've still got six more months of work to do together and refine what we were able to put together this week, because I know come Paris I'm gonna have to be a whole lot faster just to get on the podium.

"It's a good first step and test to see how our relationship is going and how things are progressing."

For the first time ever, New Zealand will have two world champion swimmers heading into the Olympic Games.

Fairweather said it was "unheard of" and "unreal" to hear the New Zealand national anthem being played twice in one week at the world championships.

She said she and the team had been inundated with support from back home during the meet.

The pair will now fly back to New Zealand and continue preparing for the Paris Olympics in July.