Jamaican sprint king injured on final leg of men's relay - while Britain's men storm to stunning 4x100 metres gold in London
World Athletics Championship: Usain Bolt's career ends in injury and agony
Usain Bolt's career dramatically ended in sorry style after the Jamaican sprint king pulled up injured on the final leg of the men's 4x100m relay final - his last race before retirement - on day nine of the World Championships in London.
Great Britain claimed the relay title just minutes after the women's squad took silver while Sir Mo Farah could only finish second in his final global track race before switching to the road.
The British quartet of CJ Ujah, Adam Gemili, Danny Talbot and Nethaneel Mitchell-Blake pipped the United States to victory in a new European record and world-leading 37.47 seconds, but only after Bolt had pulled up on his anchor leg and collapsed to the track.
The USA took silver in 37.52secs and Japan claimed the bronze.
Mitchell-Blake, who had to settle for fourth in the individual 200m, roared with delight at the finish in scenes similar to Mark Lewis-Francis' cries of triumph when he crossed the line at the 2004 Athens Olympics to earn Britain sprint relay gold.
The victory made it a night of double relay delight for the hosts as the women's team of Asha Philip, Desiree Henry, Dina Asher-Smith and Daryll Neita won silver in 42.12s.
It was one of, if not the, greatest night in the history of British relay sprinting.
The tale since Athens for Britain's men has been one of missed chances and baton blunders, including at the same stadium for the London Olympics.
But no more, and the joy among the team at a first world title in the event was evident at the finish. Mitchell-Blake was in tears and could barely speak.
The winning time, a combination of Ujah's perfect reactions, flawless changeovers and a superbly-timed dip from Mitchell-Blake to cross the line ahead of 100m silver medallist Christian Coleman, erased the 18-year-old European record of 37.73 - also held by Britain.
At the previous three Worlds Britain's men have failed to get the baton round, with team-mates turning on each other in the wake of their failure in Beijing two years ago.
But Talbot, the oldest in a young team at 26, said: "I would take all those bad times again for this one night, becoming world champions in our home country."
He added: "I think the public have probably heard enough about us being the best generation of sprinting, with no results. So it's nice we came here in front of our home crowd and did exactly what we thought we could.
"We had so much self-belief, we didn't come here to just get on the podium, we came to win and that's what we did."
US-based Mitchell-Blake, a relative newcomer to the relay squad, said: "I dreamed of this as a child. It's a sensational feeling to become world champions on home turf."
Gemili, controversially overlooked for selection in the individual 200m, said: "We just ran our hearts out, we had so much passion and the crowd just gave us an extra lift."
While Britain celebrated, though, there were contrasting emotions for Bolt in the final race of his career.
The 30-year-old pulled up on the home straight as he sought to chase down the United States and Britain, hobbling for a few strides before falling to the track.
His team-mates gathered round him and the 19-time global champion was helped to his feet and limped over the line, applauding the crowd as he did so.
"It's sad to see," Talbot said of Bolt's ending, which was put down to hamstring cramp.
"But this season is about the fans for him, it's not going to affect his legacy. He's the greatest of all time."
Britain's women finished behind the USA, who claimed gold in a world-leading 41.82s, with their silver following hot on the heels of Sir Mo Farah's second place in the 5,000m.
But while that result left a spent Farah flat on the track with his head in his hands, the emotion amongst Britain's young female sprinters as they danced with delight on their lap of honour could not have been more different. They beat Jamaican by 0.07s.
Bronze at the Olympics in Rio was a major success. This was a step up again from a team with an average age of 22.
Asher-Smith finished an agonising fourth over 200m, but silver in a season which has included a lengthy injury lay-off as she recovered from a badly-broken foot was some reward.
"I think I'm still in a dream phase, because I didn't even know if I was going to be here," she said. "To transform that to winning a world silver, which is the highest medal we have ever won, is absolutely incredible."