Keely Hodgkinson lowered her personal best and British record with a brilliant performance in the 800 metres at the Diamond League meeting in Paris.
Hodgkinson followed the pacemaker before striking for home 300m from the line, eventually clocking a time of one minute 55.77 seconds, taking 0.11secs off her previous best set in winning Olympic silver in Tokyo.
"I am a little bit shocked that I ran so fast," the 21-year-old said. "Paris next year, I will definitely be back.
"The weather was really nice, so warm. I had heard good things about the track. With this full stadium and the great crowd, it was amazing. I am so happy.
"Now the aim is to stay healthy, we still have to see, I want to keep running fast. The focus is on the summer, on Budapest (the World Championships).
"What is next with such a fast time early in the season? Well, I do not know. Hopefully I will run even faster."
Hodgkinson's record-breaking run came just half an hour after Norway's Jakob Ingebrigtsen smashed the two-mile world record by more than four seconds.
Ingebrigtsen left the field trailing in his wake as he recorded a time of seven minutes, 54.10 seconds.
The previous mark was set by Daniel Komen in 1997, three years before Olympic 1,500 metre champion Ingebrigtsen was born.
Records continued to tumble as Kenya's Faith Kipyegon set a new world's best for the 5,000m, just a week after doing the same in the 1,500m in Florence.
Kipyegon produced a blistering last lap to pull away from Ethiopia's Letesenbet Gidey and clock a time of 14:05.20, taking almost a second and a half off Gidey's previous mark.
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