Lauren Price is the fourth Team GB boxer to reach the Olympic final at Tokyo 2020 after gamely battling through her semi-final on Friday morning.
The Welsh middleweight defeated Nouchka Fontijn of the Netherlands via split decision to progress into the gold medal fight.
She will next face Li Qian of China on Sunday for the ultimate prize.
Team GB's boxers will bring home a record six-medal haul from Tokyo.
Pat McCormack and Ben Whittaker won silver, Frazer Clarke and Karriss Artingstall won bronze.
Galal Yafai, and now Price, are guaranteed at least silver and are set to fight for gold medals.
"Each fight gets harder and it doesn't get harder than that today," said Price. "We're No 1 and No 2 in the world, we've met so many times.
"It's nothing new to me going into a final. I've been here before, Wales, Europeans, it's nothing new to me. It's everyone's dream to get to that Olympic final and I'll do my best to bring back that gold."
Price, the No 1 seed in her division, is also a four-time kickboxing world champion and has earned 52 caps for Wales as a footballer.
As a boxer she has won gold medals at the World Championships, European Games and the Commonwealth Games and could now complete a remarkable set if she wins the Olympics.