British relay team revel in golden moment as Bolt suffers sad exit

But this, this was the most gloriously bonkers story yet. Not even Danny Boyle at his most creative could have crafted this one and writing it down in black and white doesn't make it seem any more unbelievable.

Shocked and in awe, the home crowd watched as Great Britain's men's 4x100m quartet stormed to the world title.

And then - barely knowing how to react - they witnessed Bolt's last-ever track race end with him briefly in a wheelchair and hobbling off the track.

No-one watching quite knew where to look or what to say, so they just lost themselves in the heady and intoxicating atmosphere, which no stadium does quite like this place.

It was a rollercoaster evening of emotions, with tears and cheers measured in equal number, those here will never get tired of retelling a story that had it all.

Mo Farah's track farewell ended with a silver in the 5,000m, his first defeat at this level in 2176 days.

And then came silver for Great Britain's women's 4x100m team before the final race, which was due to be all about the legendary Jamaican, with the host nation cast purely in a supporting role.

But they had no intention of being a footnote to this tale and CJ Ujah got Britain off to a flying start before a seamless changeover to a surging Adam Gemili. Danny Talbot ran a textbook bend and smoothly unloaded to Nethaneel Mitchell-Blake on the anchor leg.

He didn't look left, he didn't look right, he simply charged down the track towards the line and left the rest of the world in his super-charged wake. Stunning.

American Christian Coleman chased him hard but was always sniffing his vapours, as Mitchell-Blake flashed across the line in a new 37.47 second European record, carving nearly a quarter of a second off the previous 18 year old mark. Cue scenes of pure and unadulterated bedlam.

Japan took bronze while Bolt pulled up 50 metres from the line, the saddest end to the most glorious of careers.

But for Gemili and Talbot the win was extra special. Five years ago it was their changeover that disqualified Team GB at the Olympics, but those memories were happily and gloriously exorcised.

"This is a dream. Is it true? Is this actually happening to me?" said a stunned Gemili. "This is just crazy, I don't anything will ever be as special as this, it's just not happening is it?

"We are world champions, I'll never get bored with saying that. And to do it with Danny after what happened in 2012, that's make this even more amazing, even more special."

Talbot even claimed the foundations for this success were laid five years ago, after that failure on the same track. If revenge is a dish best served cold, they patiently waited before dishing out their rivals liberal double helpings.

"2012 didn't go our way and we have been working hard since then," he said.

"It's a massive team effort and we win as a team and lose as a team. We are world champions at home. We will never get this feeling again."

The quartet spoke as quick as they ran, starting sentences and then stopping suddenly and talking over the top of each.

"I am proud of these guys and those behind the scenes, this is for them," said Ujah, whose flying lead-off leg established a British lead they never lost.

"It is crazy to do this in London but I can't even talk right now, my head is all over the place and the words aren't coming out properly."

This is Great Britain's first global relay success since they struck an equally improbable sprint relay gold at the Athens Olympics 14 years ago. And it's their first world title since the 4x400m quartet won in Tokyo 26 years ago.

British sprinting certainly looks in rude health at these championships. With a gold and silver in the sprint relays and three impressive finalists at the start of their careers - Reece Prescod, Dina Asher-Smith and Mitchell-Blake.

And he admitted he had no idea of the result until the scoreboard flashed up the winning time.

"I wasn't sure if I had won or not," added Mitchell-Blake. "I gave it my all but I could see Christian Coleman out of the corner of my eye. The feeling of euphoria was from infinity. I can't register it. We smashed the British record to pieces, it's just remarkable." Britain's fast girls Asha Philip, Desiree Henry, Dina Asher-Smith and Daryll Neita flew to an impressive silver as 100m champion Tori Bowie survived a shaky final changeover to run a decisive anchor leg for the United States.

And there is more to come from a quality quartet that is certainly tracking on the right trajectory. After bronze at last year's Olympics, they claimed silver in London. And there is room for improvement, their time from Rio would have won them gold here.

"I’m still in a dream, this is our highest ever medal, it’s just incredible," said Asher-Smith, who only returned to action two months after ago breaking her foot. I’m just in a dream state right now, you should never give up."