Becky James became a double world champion and the first British rider to claim four medals at a world championships by winning gold in the women's keirin in Minsk.
The 21-year-old from Abergavenny led from start to finish in a dominant victory that took her tally to two golds and two bronzes at a championships that have announced her as one of the best sprinters in the sport.
James surged off the start line to take up the first spot behind the motorised pacer and never relinquished it, holding off late counter-attacks to beat China's Jinjie Gong into second place and Cuba's Lisandra Guerra Rodriguez into third.
Her main rival for victory, Germany's Kristina Vogel, did not finish after crashing as the chasing riders jostled for position.
The win completed a breakthrough week for James, where she also claimed gold in the individual sprint and bronzes in the team sprint and 500m time trial.
It also ensured Britain topped the medal table in Minsk with five golds, two silvers and two bronzes. James on her own would have finished joint-fourth.
"It doesn't feel real to me," she said. "I just wanted to defend that first place and I knew if I stayed there, it would be a struggle for everyone else to get around.
"I just really dug in - that hurt so much. I can't believe that just happened. It's going to take a while to sink in but it means so much. Two worlds jerseys - I'm chuffed to bits."
James, appearing in her third senior world championships, won a medal a medal in every event she entered in Minsk.
She progressed to the keirin final earlier on the last day of competition with a confident and composed ride. Despite being boxed in and looking out of contention going into the final of lap, she powered through a small gap and qualified safely in second place.
Trott edged out
There was no second gold medal of the championships for Laura Trott, though, after she was dethroned as world omnium champion by Sarah Hammer and had to settle for silver.
Trott finished the six-event competition four points behind the American, with Australia's Annette Edmondson claiming bronze two points further back.
Olympic champion Trott was third overnight after three events, but saw her chances of retaining the rainbow jersey slip away when Hammer won the first event of the second day, the individual pursuit.
Third places in that event and then subsequent scratch race saw Trott move into second overall, but Hammer's fourth in the scratch race left the Briton needing an unlikely sequence of results in the concluding 500m time trial to salvage victory.
A fourth place in that event was insufficient, leaving Hammer to claim her second gold of the championships, having already won the individual pursuit on the opening day.
Trott, whose challenge was ultimately undone by a 10th in the points race on day one, said: "I did my best but the better rider beat me on the day. After [the points race] I didn't even think I would get a medal, so to come away with silver, I'm super-happy."
Elsewhere on the final day of the championships, Germany's Stefan Botticher defeated Russia's Denis Dmitriev 2-0 to claim gold in the men's individual sprint. France's Francois Pervis overcame New Zealand's Sam Webster to take the bronze.
In the men's madison, Great Britain's Owain Doull and Simon Yates could only finish 11th as France took gold, Spain the silver and Germany the bronze.