Dame Sarah Storey claimed Great Britain's first medal of the 2014 World Para-cycling Track Championships in Mexico with bronze in the C5 500m time-trial.
Team-mate Crystal Lane was fourth, four tenths of a second behind, as China's Ju Fang Zhou won gold ahead of the USA's Jennifer Schuble.
Britain has sent an 11-strong team to the championships.
Lora Turnham and pilot Corinne Hall finished fourth in the tandem B 3km pursuit, just missing out on bronze.
Storey, 36, an 11-time Paralympic gold medallist, only returned to action in December following the birth of daughter Louisa in June.
Eight world records were broken on day one in Aguascalientes, including Zhou's time of 36.379 seconds.
Storey, who came home in 37.154, was "really chuffed" with her time, which was just two tenths slower than she clocked at London 2012.
"I've had a lot less training over the winter than I usually would have," she added. "It's brilliant to be back and back on the podium."
Lane had been made to dismount on the start line while officials debated the legality of her hand brace.
"The officials were checking the brace was safe and would detach from the bike should she fall," said Great Britain Paracycling coach Jon Norfolk. "Unfortunately, they chose the start of the race to check, so we had to start preparations again which wasn't perfect."
As Turnham and pilot Hall lost out to Japan in the bronze medal race for blind and visually impaired riders, the New Zealand pair of Emma Foy and pilot Laura Fairweather broke the world record not once but twice.
They chopped more than eight seconds off the previous time of three minutes 31.53 seconds to win gold in 3:23.328.