ParalympicsGB claimed their first gold medal of the Paris Games as swimmer Poppy Maskill broke a world record in the women's S14 100m butterfly final, before Tully Kearney followed her team-mate in taking victory.
Maskill recorded a time of one minute and three seconds, breaking the previous record by a third of a second.
“It was so hard,” Maskill told BBC. “I was just trying my hardest not to die. I was just trying to see how I could do compared to this morning. It’s weird, it’s really cool. It’s just unreal.”
Shortly afterwards fellow Great Britain swimmer William Ellard took silver in the men's S14 butterfly final.
Kearney then took the S5 200m freestyle crown in 2:46.50, upgrading the silver she won at Tokyo 2020. The victory secured a second career Paralympic gold for the 27-year-old, who is reigning S5 100m freestyle champion.
She held off the challenge of Ukraine's Iryna Poida and Italian Monica Boggioni to win the final race of the opening day of the Games.
Having suffered a head injury last year, Kearner was still unsure if she would compete in France as recently as a fortnight ago.
"I really wanted redemption for Tokyo," said Kearney, who was born with cerebral palsy and developed generalised dystonia - a neurological movement disorder characterised by continuous or intermittent muscle contractions - as a teenager.
"I was never happy with that silver, so to go and get gold in the 200m freestyle was just incredible. It's been really hard with the concussion and then the last three, four months, really hard with mental health issues.
"Even a few weeks ago, we weren't sure whether I was going to come out and compete or how many events I'd be able to do. I'm just absolutely ecstatic. A bit speechless."
The first medal of the Games came in the women's C1-3 3000m individual pursuit, with Daphne Schrager winning silver.
Tandem duo Steve Bate and Chris Latham later won silver in men's B 4000m individual pursuit.
Bate said afterwards: “If this is my last event, a hell of a way to go out. Everything has been geared towards this event, I haven’t thought much beyond that.
“I’ll get the two road events out the way, take some time off and see where we are at.”
