Great Britain won double tandem gold and set two world records in the process on the second day of the UCI Para-cycling Track World Championships in Aguascalientes, Mexico.
Sophie Thornhill and pilot Rachel James, in their first world championship, rode to 1:05.912 in the women’s tandem B one-kilometre time-trial, nearly two seconds quicker than silver medallists Australia.
James, 26, and Thornhill, 18, have been riding together for less than six months.
Paralympic champion Neil Fachie and pilot Peter Mitchell became the first tandem team in history to break the one minute mark in a time of 59.460 seconds.
The previous record of 1:01.351 was set by Fachie and Barney Storey at the London Paralympics.
"To think this is our first race at a major championships, and we won it, I still can't believe it," Thornhill, from Cheshire, told BBC Sport.
"We knew the record was on the cards but to break it by almost three seconds is amazing."
Fachie tweeted: "Today I achieved one of my major goals, to be on the first tandem to break the 60 second barrier for the 1km TT, 59.4 and world champion :)."
Jon-Allan Butterworth added Britain’s fourth medal in the competition with bronze in the men’s C5 four-kilometre pursuit.
The 28-year-old, a three-time silver medallist at the London Paralympics, defeated Italian Andrea Tarlao in the bronze medal ride-off.
Ukrainian Yehor Dementyev took silver and Australian Michael Gallagher gold.
Shaun McKeown was forced to settle for sixth in the men’s C3 three-kilometre pursuit as Russia’s Alexey Obydennov took victory.
Jody Cundy, twice a Paralympic gold medallist on the track, ended the men’s C4 four-kilometre pursuit in 10th, Slovakia’s Jozef Metelka setting the winning time.
The three medals won take Great Britain's total to four after Sarah Storey's C5 500m time-trial bronze on day one of the competition, which finishes on Sunday.