Olivia Breen won the T38 long jump to secure a ninth gold medal for Great Britain at the World Para-athletics Championships in London.
Breen, 20, who has cerebral palsy, recorded a personal best of 4.81m to claim a first individual major title.
Britain's Sophie Kamlish set a new T44 world record of 12.90 secs in the T43/T44 100m heats.
Britain are leading the medal table with 16 in total, including two silver and five bronze.
Wales' Breen, who won a gold medal in the 4x100m relay at the 2015 World Championships, only finished 12th in the long jump at the Paralympics Games last year.
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Monday's result, which saw her finish ahead of Australian Erin Cleaver and Anna Trener-Wierciak of Poland, marked an incredible turnaround in her career and came in front of an ecstatic London Stadium crowd, with 29,000 school children in attendance.
"I've moved to Loughborough to train. I knew I had to change something and it's been the best change ever. This is a dream come true," Breen told BBC Radio 5 live.
"I'm so happy. I knew I had to be on my form and it's so exciting."
Aled Davies and Jonnie Peacock had taken Britain's tally to eight golds on Sunday's third day.
World record for GB's Kamlish
Elsewhere, America's seven-time Paralympic gold medallist Tatyana McFadden continued her domination of women's T54 wheelchair racing by winning the 1500m - her second victory of the championships and 12th career world title.
After claiming gold in the 200m on Friday, she can add the 400m on Monday night and could complete the quadruple in the 800m on Wednesday.
Sprinter Kamlish will be joined by team-mate Laura Sugar, who came third in her heat, and defending champion Marlou van Rhijn of the Netherlands in Monday night's T43/T44 final.
"I didn't think I'd get a world record because I slowed down at the end. It felt like I was walking when I knew I had qualified," said the 20-year-old, who has a below-the-knee amputation to her right leg, after taking 0.03 secs off her previous mark, set at the Rio Paralympics.
Britain's Richard Whitehead, who secured T42 200m gold on Saturday, won his 100m heat to progress into Monday night's final as he looks for a first major medal in the shorter distance.
Team-mate Dave Henson, bronze medallist in the 200m, missed out and afterwards said his right prosthetic blade had come loose, caused by the sweat on a warm day in London.
Richard Chiassaro made sure there will be British interest in Monday night's T54 800m final by progressing as a fastest qualifier, but Nathan Maguire misses out after coming fifth in his heat.
GB's F34 shot put athlete Vanessa Wallace threw a personal best of 7.64m on her way to a fifth-placed finish and Martina Barber put in a career best leap of 5.17m in the T20 long jump as she finished fourth.