The 19-year-old earned a new personal best score of 76.93 points after a flawless routine to "Exogenesis Symphony Part 3" by Muse.
The 2019 world bronze medalist produced a triple flip-triple toe, double Axel and triple loop to finish ahead of teammate Alexandra Trusova (74.21), and USA's Mariah Bell (67.11), but still the one person Medvedeva was hoping to impress was her coach.
"I am happy with my skate, because it finally worked out the way it should," Medvedeva said.
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"I hope that everyone has seen my work and Brian (Orser, coach) is happy. It was the right decision (to return to the triple loop). I've done that before and every time I did it, my points went up."
After a Russian one-two-three earlier in the day in the men's short programme, there was further home success with another one-two-three in the pairs - Aleksandra Boikova and Dmitriy Kozlovskiy claiming top spot with a score of 80.14.
In the ice dance, the Russian pairing of Victoria Sinitsina and Nikita Katsalapov also finished first with a score of 86.09.
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