The 26-year-old raced to victory in 12.09 seconds at the Weltklasse Zurich meeting on Thursday, taking three hundredths of a second off the Nigerian’s previous world record of 12.12, set at the 2022 World Championships in Eugene, Oregon.
Russell produced a faultless performance over the barriers, quickly establishing her advantage before powering across the finish line in record time.
Impressively, her effort came with zero wind, making the achievement even more remarkable.
Amusan, meanwhile, finished second in a season’s best of 12.23 seconds, while European champion Nadine Visser of the Netherlands took third in 12.34.
Russell had threatened to break Amusan’s record throughout the season, having previously recorded the second- and third-fastest legal times in history with 12.14 and 12.17. She also clocked 12.19, further underlining her growing dominance in the event.
The Olympic reigning champion celebrated her historic achievement by placing her index finger over her closed mouth in a shushing gesture as she came to a stop.
Russell’s performance made her the new world record holder and American record holder in the event, subject to formal ratification by World Athletics.
Even at this, Amusan still owns the fastest time ever recorded under any conditions, having run 12.06 at the 2022 World Championships. That performance was aided by a 2.5m/s tailwind, exceeding the 2.0m/s legal limit for record purposes.
Prior to the race, the Nigerian sprint sensation had won bronze in the women’s 100m hurdles at the recently concluded Commonwealth Games in Glasgow, finishing behind gold medallist Devynne Charlton and silver medallist Megan Simmonds.