Ellie Simmonds and Bethany Firth both broke world records at the British Para-Swimming International Meet in Glasgow as their preparations for Rio 2016 continued.
Simmonds, who won two golds at both the Beijing and London Paralympics, took a second off her S6 world record in the 400m freestyle after clocking five minutes and 18.69 seconds.
"I knew I had that in me, training was going really well leading into the competition, but I am so happy," said Simmonds.
"It is great for me to get that time and great for my positivity.
"I will look back now and see what I can improve on and what did go well and what didn't.
"I've just got to focus on myself in training now. I have got tons of rivals out there, but I've got to go out there in Rio and swim the best that I can."
S10 swimmer Rosie Bancroft took silver in a time of 4mins 49.52secs, while bronze went to Ellie Robinson in 5:48.72.
Firth, meanwhile, lowered her own world mark in the S14 200m freestyle with a swim of 2:03.70, which is under the qualification consideration time for the Rio Paralympics.
"Words can't really describe how I feel right now," Firth said. "I was praying throughout that whole race, I was just hoping that I could do a good time and show people that I've come here to mean business."
Silver went to Paralympic champion Jessica-Jane Applegate in 2:05.63, again putting the S14 Norwich swimmer in contention for the British squad this summer, while Chloe Davies claimed bronze in 2:13.26.
In the men's S14 200m freestyle, Tom Hamer set the qualification time needed for Rio in the heats with a British record of 1:57.27 before going on to take gold in the final with a swim of 1:57.49.
Paralympic gold medalist Ollie Hynd won the final event of the evening after finishing the 400m free in a time of 4:24.69, just outside of his own world record, but crucially under the Paralympic consideration time.