Becky James won her first senior world title with a thrilling victory in the women's individual sprint at the Track Cycling World Championships in Minsk.
The 21-year-old came from behind to beat Germany's Kristina Vogel 2-1 and claim a gold medal to add to the two bronzes she won earlier in the week.
She lost the first race of the best-of-three final in a tight photo finish, but then confidently took control of the contest.
James first levelled in race two, allowing Vogel to lead out the sprint before storming around the outside of the German, and then sealed the title in race three by attacking early and holding on for a comfortable win.
She takes over the world sprint title from Victoria Pendleton, who won it in Melbourne last year, and in doing so has announced herself as a world-class sprinter with one of the brightest futures in the sport.
"It's just not sinking in," James said afterwards. "I had targets in my head - I wanted to get top eight in everything - but to be standing on that podium tonight, it's such a good feeling."
James' bronzes came in the team sprint and individual 500m time trial, and her latest medal takes Britain's tally of golds to four for the championships.
There will be no sprint medal for Jason Kenny, though, after the Olympic champion was surprisingly beaten 2-0 at the quarter-final stage by 21-year-old New Zealander Sam Webster.
Kenny had progressed to the last eight by defeating Pavel Kelemen (Cze) in round one and then Stefan Botticher (Ger) in round two, but was soundly beaten by Webster in both races of their quarter-final.
Webster will now face Botticher, who progressed to the quarters by virtue of a repechage, in Sunday's semi-finals, with Francois Pervis (Fra) facing Denis Dimitriev (Rus) in the other last-four clash.
Although Kenny will not be on the podium, Laura Trott is on course to win a medal in the women's omnium.
The defending champion started the six-race event well with a third place in the flying lap, before a less impressive 10th in the points race saw her drop to fifth overall.
But she bounced back brilliantly in the third event of six, winning the elimination race to move into the bronze medal position with three events remaining on Sunday. The United States' Sarah Hammer is the overnight leader.
Dibben digs in
Jon Dibben ended the men's omnium in an impressive eighth place on his world championship debut. Having won the fifth of six races, the scratch race, earlier in the day, the 19-year-old then posted the 12th best time in the concluding 1km time trial.
The gold was won by New Zealand's Adam Gate, with Olympic champion Lasse Hansen (Den) taking silver and Glenn O'Shea (Aus) bronze.
Dibben said: "I am happy with the way it has gone. Eighth is a solid result for me. The omnium is hard - six races in two days. You never have too much time lying around. You have to stay on your toes and try and take it in your stride."
In the women's points race, Dani King was unable to repeat the heroics of compatriot Simon Yates 24 hours earlier in the men's version, finishing eighth, having never really threatened the top of the standings. Jamila Machacova (Cze) took gold, ahead of Sofia Arreola (Mex) in second and Georgia Bronzini (Ita) in third.