Britain's Lauren Price became the first Welsh fighter to win an Olympic boxing gold medal as she beat China's Li Qian in the women's middleweight final.
Price, 27, gained a 5-0 points victory at the Kokugikan Arena in Tokyo to earn Britain's 22nd gold of the Games.
She becomes the second British woman to win boxing gold after Nicola Adams' flyweight successes in 2012 and 2016.
Britain have won 65 medals in Tokyo, matching their London 2012 total, with 22 golds, 21 silvers and 22 bronze.
- Tokyo 2020 medal table
- Who won GB's medals?
- Team GB athletes' results
"I can't really put it into words - it's a dream come true," Price told BBC Sport.
"I still have to pinch myself. It's been years of hard work and if you dream and work hard enough you can achieve anything.
"I'm just over the moon and I want to thank everyone who supported me on this journey from eight years old."
Price's grandfather Derek passed away in November and, in an emotional interview, Price dedicated her gold medal to him and also to her grandmother Linda.
"It's for him and my nan - I knew he would be looking down on me today and all week really," said Price, who was raised by her grandparents from three days' old.
"I can't really put into words what they've done for me over the years, I just love them both so much.
"Big shout out to my nan, I can't wait to see her and show my medal off."
Incredible athlete Price makes history
Price, who has played international football for Wales and been a world kickboxing champion, won the opening round against former world champion Li with all five judges, able to pick off punches against her taller opponent thanks to quick hands and feet.
She continued to dominate in the second round, controlling the pace and tempo with her 31-year-old opponent struggling to land. Four of the judges gave that round to Price, meaning Li needed a stoppage or knockout in the final round.
But Price was never in danger in the third as her near-flawless performance gave her a 30-27 winning margin on four judges' scorecards and a 29-28 victory on the other one.
Adams, watching from the BBC studio, said Price had been an overwhelming winner.
"Lauren had her tactics spot on and Li just couldn't cope," said the double gold medallist. "She made it look easy - it was like watching a spar.
"She dealt with all the pressure really well."
Price had already become only the third Welsh boxer to win an Olympic boxing medal after Fred Evans won welterweight silver at London 2012 and Ralph Evans won a light-flyweight bronze at the 1972 Games in Munich.
The Newport-born fighter has also represented Wales at international level in different age groups in netball and taekwondo and won world, European and British honours in kickboxing.
She played 52 times as a defender for Wales' national football team across the age groups - winning two senior caps - before she focused on boxing.
She quickly set history by becoming the first Welsh woman to win a Commonwealth Games medal with a bronze in Glasgow in 2014, before taking gold four years later on Australia's Gold Coast and then winning a World Championship gold medal in 2019.
GB end boxing event with six medals, including two golds
Price's gold was Britain's second in the ring in Tokyo following Galal Yafai's win in the men's flyweight competition on Saturday.
Pat McCormack (men's welterweight) and Ben Whittaker (men's light-heavyweight) both won silvers while Frazer Clarke (men's super-heavyweight) and Kariss Artingstall (women's featherweight) collected bronze medals.
It means Team GB won six medals - two gold, two silver and two bronze - from their 11-strong team, the most British boxing medals at a Games since Antwerp in 1920, although they did win three golds at London 2012.
Earlier on Sunday, Ireland's Kellie Harrington beat Brazil's Beatriz Ferreira in the women's lightweight final.
Harrington, 31, who works as a cleaner at a hospital in Dublin, became the second Irish woman to win boxing gold after Katie Taylor took lightweight gold at the 2012 Olympics in London.
It was a superb performance from Harrington, who collected a unanimous points victory, with two of the five judges giving her the win by 30-27 margins, and the other three scoring it 29-28 in her favour.
- Team GB Takeover: Find out these athletes' favourite One Hit Wonders
- Homegrown Heroes: How it all started for Blossoms and why they are still true to Stockport