Jody Cundy secured his 13th track world title with victory in the C4 kilometre time trial at the Para-cycling World Championships in Los Angeles.
The 38-year-old is unbeaten in world kilometre events since 2006.
Cundy was the last of 11 riders to set off, posting a time of one minute 05.614 to beat Slovakia's Jozef Metelka by more than half a second.
"Even though I'm not in the best shape ever I still managed to produce the goods," Cundy told BBC Sport.
"I don't know if it's because I'm getting older or the seven weeks' preparation - probably both - but I really struggled when I got off the bike.
"But everyone was in the same boat and it came down to who wanted it the most."
Team-mate Jon Gildea, racing in the C5 category, took silver, with his preferred event, the individual pursuit, to come on Saturday.
The medals take Great Britain's tally in Los Angeles to two golds and two silvers.
After winning his second World Championships silver medal, Gildea has the chance to win a maiden world gold on Saturday.
"It's about the jersey more than the medal for me - I really want a world champion's jersey," Gildea said.
"It's a really big deal for me and I'm in good nick."
Also in action on Saturday are all four women's tandems and both men's pairings - all in the kilometre time trial.