Dina Asher-Smith won the 200m in a season’s-best time of 22.06 seconds at the Diamond League meeting in Florence.
Asher-Smith, the 200m world champion, powered to a commanding victory – her time 0.03secs outside the fastest this year, run by Shaunae Miller-Uibo.
The Briton, 25, has already won twice in the 100m this season as she builds towards the Olympic Games in Tokyo, which begin in July.
Laura Muir came third in a stunning 1500m race won by Sifan Hassan.
Britain’s European champion Muir, Kenya’s Olympic champion Faith Kipyegon and world champion Hassan of the Netherlands were all in contention in the final lap.
Hassan, who smashed the 10,000m world record last week only for it to be beaten two days later, held off Kipyegon in a sprint finish, running a world-leading time of 3:53.63 – the eighth-fastest time in history.
Muir lost ground with 200m to go but still ran 3:55.59, the second-best time of her career and a season’s best.
Elsewhere, Norwegian 20-year-old Jakob Ingebrigtsen stormed to a brilliant win in the men’s 5,000m, setting a new European record of 12:48.45.
Britain’s Andrew Pozzi ran a season’s best in the 110m hurdles but was beaten by Jamaican Olympic champion Omar McLeod who ran the fastest time in the world this year.
South African Akani Simbine edged out Britain’s CJ Ujah in the 100m to win in 10.08secs.