Lewis Clareburt smashes NZ record, proves Olympic medal potential

Wellington swimmer Lewis Clareburt has smashed the New Zealand Open record in the men's 400m individual medley as he prepares for his Olympic debut in Tokyo.

Lewis Clareburt. Source: Photosport

The 21-year-old swam an incredible 4:09.87 at the national championships last night, two seconds faster than the previous record he also holds, 4:12.07.

His time was nearly six seconds faster than the Olympic standard set for the event, and a strong showing just months out from the Tokyo Olympics.

Clareburt had swum seven seconds slower in his heat earlier in the day, and was pleased to be able to put in a much stronger performance in the final.

"I felt shocking this morning so to look up and hear the 4:09 was pretty cool," Clareburt said.

"I heard the crowd the whole way which was awesome and I think that's what the difference was."

Clareburt's time was just milliseconds slower than the bronze medal time at the Rio Olympics, and while he proved he could be in with a shot at breaking New Zealand's 25-year medal drought in the pool, he said he still had plenty of work to do.

"I always swim better in the afternoon but come Tokyo we're swimming the finals in the morning, so I really need to sort that out."