LONDON - Pierre-Ambroise Bosse loves gambling and on Tuesday he rolled the dice and won the biggest prize of his life.

The 25-year-old Frenchman won the 800m world title to give France its first ever gold in the event.

Bosse, who finished a valiant if frustrating fourth in the final at last year's Rio Olympics, seized the initiative with 150 meters to go with a stunning burst passing Kipyegon Bett and favorite Nijel Amos, then held on to hit the tape just ahead of fast-finishing Adam Kszczot of Poland.

"I'm a gambler, I love going to the casinos," said Bosse.

"And today I just gambled, I put everything on the red. So hopefully, this is also for luck in love."

Bosse, renowned for his offbeat character, addressed his cat 'Rabs' after finishing outside the medals in Rio by telling the animal to go the fridge and help himself to a beer.

He said he thought he had cast a spell over his rivals as no one threatened him down the final 100m.

"It felt like I was being chased in a nightmare," he said. "It was never-ending. I could not understand why nobody was going past me.

"Even when I crossed the line, I could not believe it.

"The others killed themselves and they were already dead in the last 100m. I was like a witch casting a spell on them."

Bosse, who along with a friend launched a dating app called Deserve Her earlier this year as a rival to Tinder, said he had felt like a kid who would do anything to have the toy he wanted.

"It was a war of attrition," said Bosse, who revealed he had spilled a bottle of water on his bed on Monday when he was fantasizing about winning the gold medal.

"I felt like a little boy who wanted this toy and I said to myself: 'In any case you have nothing to lose'.

"As I went past the others, I put myself in their place and said to myself: 'What must they be thinking? I thought they are going to pay for this and that pleased me'.

"It is the first time in my career I have felt like that.

"Finally today I was ahead of everyone. People can forgive me now because I now have that world title."

Away from the track, Bosse plays guitar - largely tunes by legendary French poet and songwriter Georges Brassens. He said he thought he was seeing things after he went on his lap of honor and spied his best friend in the crowd.

"He had a date with a girl in the south of France yesterday and we spoke to each other on the phone last night," said Bosse.

"He wished me the best of luck and I thought I'd see him again in France. Then tonight, I see him in the crowd and I was so pleased."

However, any thoughts of going out and celebrating with him are on hold.

"I had to pinch myself really hard to realize that I had really won," he said.

"Very soon after, I was throwing up. I cannot party like Usain Bolt."

Agence France-presse