Phoebe Paterson Pine struck Paralympic archery gold after winning the battle of the Brits by eliminating defending champion Jess Stretton en route to glory in Tokyo.
Games debutant Paterson Pine began a memorable day with a tense 141-140 success over her world number one compatriot in the second round of the women's individual compound.
The 23-year-old, who has spina bifida, later took Stretton's crown with a 134-133 win over Chile's Mariana Zuniga Varela in the decisive contest, having also beaten France's Julie Chupin and Italian Maria Andrea Virgilio in the quarter-finals and semi-finals respectively.
Stretton won gold in Rio aged just 16 and was favourite going into the match after seeding first in ranking, which included a Paralympic record score.
Former swimmer Paterson Pine, who began her current sport on a family holiday to Centre Parcs during the London 2012 Olympics, was initially disappointed with her final arrow at Yumenoshima Final Field before realising it was sufficient for gold.
"I'm really bad at maths so I had no idea what I actually needed," she said.
"I saw I shot an eight and was like, 'Oh my goodness, I shot an eight. That's horrible'. And then I realised I needed that to win and thought, 'Maybe that's not too bad'.
"I naturally cannot keep up with score but that's kind of good in a way. It means I didn't have to sit there and think, 'I need to hit this'. I was able to go through my normal process and do my shot routine.
"I still almost feel I'm living in a dream and it won't settle until I'm with family or looking at the aftermath on my phone."
Elsewhere on Monday, powerlifter Louise Sugden won bronze in the women's -86kg division.
Former wheelchair basketball player Sugden's best lift of 131kg was the same as fourth-placed Egyptian Amany Ali but the 37-year-old Briton took the podium place due to being more than a kilogram lighter than her rival.
