Femke Bol of the Netherlands has shattered her own indoor 400 metres world record to take gold at the global championships in Glasgow.
The 24-year-old clocked 49.17 seconds on Saturday, lowering the previous mark of 49.24 she set two weeks ago at the Dutch national championships, to claim the first world record of the three-day event.
The dynamic Dutchwoman captured gold in the 400m hurdles and 4x400m relay at the outdoor world championships last year in Budapest and is a red-hot favourite going into the Olympic Games in Paris later this year.
Her teammate Lieke Klaver took the silver on Saturday in 50.16, while American Alexis Holmes ran 50.24 for bronze.
"It was such a strong race, I knew I had to go out fast," Bol said.
"My coach said to me, 'You can run faster', but to be honest I just wanted to win.
"It is just great to race and this competition and the atmosphere has been amazing."
Outdoor 1500m world champion Josh Kerr ended Scotland's 31-year wait for a global indoor title, winning the 3000m gold on home ground.
Kerr powered away on the final lap to win comfortably in seven minutes 42.98 seconds, with defending champion Selemon Barega of Ethiopia fading down the final straight as he was beaten to silver by American Yared Nuguse.
After disappointment for local favourite Laura Muir in the women's 3000m final earlier in the evening, Kerr's victory sparked huge celebrations at Glasgow's Emirates Arena.
"I think I burned more energy celebrating than I did in the race, which is a bit embarrassing," Kerr told BBC Sport.
"This competition is so important.
"I came in without a solid plan, just really fluid. I wanted to make sure I wasn't acting emotionally.
"I kept a patient head and then I could really send it with 400 metres to go."
The women's 3000m was won by US athlete Elle St Pierre in a championships record time of 8:20.87, ahead of Ethiopia's Gudaf Tsegay.
Kenya's Beatrice Chepkoech was third, edging out Australia's Jessica Hull for bronze.
Molly Caudery delivered a second British gold of the night in the women's pole vault, taking the win after New Zealand's Eliza McCartney was unable to clear the bar at 4.90m.
The competition had been delayed by a terrible fall for France's Margot Chevrier, who suffered a suspected broken ankle.
Belgium's Alexander Doom caused an upset as he beat Karsten Warholm in the final 50m to take men's 400m gold, while Grant Holloway delivered gold for the USA in the men's 60m hurdles and Burkina Faso's Hugues Fabrice-Zango won the men's triple jump.
Julien Alfred delivered Saint Lucia's first ever world indoor medal with gold in the women's 60m final, edging out Poland's Ewa Swoboda
At 19 years and 26 days, Italy's Mattia Furlani became the youngest long jump medallist in World Indoor Championships history, claiming silver in the men's event with a leap of 8.22 metres.
The teenager missed out on the title - to Greece's reigning Olympic and world outdoor and indoor champion Miltiadis Tentoglou - on countback, with bronze going to Carey McLeod of Jamaica (8.21m).
- with PA
