Duplantis then beat his own world record of 6.20m - set in Belgrade in March - at the second attempt.

It is the fifth time he has broken the world record.

His success marked the first time the record has been set outdoors since the legendary Sergey Bubka cleared 6.14m for the first time in Sestriere, Italy, in 1994.

Duplantis, who grew up in Louisiana, celebrated with a front flip in front of a packed crowd, kissed girlfriend Desire Inglander, before being embraced by his father Greg, a former top-class pole vaulter himself.

"It was something that I really wanted and needed," Duplantis said to BBC World Service of the one major medal missing from his collection.

"I was so caught up in trying to win and capture the gold that honestly the world record thing was just an afterthought.

"It didn't cross my mind during the competition because I just wanted to win so badly.

"To be able to do it in the fashion I did is very special. It is something I am very grateful for."

Asked how high he could potentially push the record, Duplantis added "there is definitely more".

"It doesn't feel like I have maxed out what I can do yet. As long as I feel I can keep pushing boundaries, the motivation is still going to be there. Plus I am having fun doing it," he said.

Nigeria's Amusan breaks 100m hurdles world record

It was the second world record set on the final day of competition at the World Championships in Eugene.

Earlier, Nigeria's Tobi Amusan broke the 100m hurdles world record as the semi-finals delivered an extraordinary set of times.

The 25-year-old, who ran a new African record of 12.40 seconds in Saturday's heats, clocked 12.12.

Her time beat the 12.20 set by American Kendra Harrison, who finished second behind Amusan, in 2016.

"I wanted to get out and go," said Amusan. "I did what I had to do.

"I believe in my abilities but I was not expecting a world record at these championships."

Amusan went on to win gold in the final, two hours later.

But her winning time of 12.06 - which would have been another new world record - was ruled ineligible by a tailwind over the legal limit.

Great Britain's Cindy Sember finished fourth in the semi-final won by Amusan, but qualified for the final with a British record of 12.50, beating sister Tiffany Porter's 2014 mark by one hundredth of a second.

It was one of four national records, excluding Amusan's, run in the semi-finals, with another seven athletes equalling or breaking their personal bests.

"That was a crazy race. I actually thought I was running slow. Tobi was amazing, I can't deny," said Sember, who went on to finish fifth in the final.