Keely Hodgkinson broke Kelly Holmes' 800m British record to win a brilliant Olympic silver - Team GB's first athletics medal of Tokyo 2020 - behind American Athing Mu.
Both 19-year-olds showed they could develop a fascinating rivalry in a stunning race, which produced heartbreak for Jemma Reekie, who was beaten to bronze by Raevyn Rogers.
Mu broke the American record by running 1:55.21 ahead of Hodgkinson's 1:55.88, which made the teenager from Wigan Britain's first Olympic medallist over the distance since Holmes' gold at Athens 2004.
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Alex Bell, who was working in a sports shop before she was called up as a late replacement when Laura Muir decided to concentrate on the 1500m, produced a personal best but could only finish seventh.
It was the first time that three British women had qualified for an Olympic final and the race did not disappoint. Of the eight competitors, only two were not able to produce a personal best.
Mu took the initiative from the start and was never in any serious danger of being caught, but Hodgkinson made her move on the home straight.
'Wow, what a race!' - Hodgkinson with 'stunning performance' to claim 800m silver
Reekie was second at the final bend, but her team-mate and European Indoor champion streaked past her with some 80m to go. Reekie, though, faded badly with Rogers overtaking her for third place with around 5m to go.
But the race was one of the most fiercely contested of the athletics programme so far, dominated by two teenagers with a bright future in the sport.
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