Konkoly entered the meet with the event's third best time in the world this year with a mark of 29.38sec, trailing only Spain’s Sarai Gascon and former world record holder Ellie Cole of Australia.

She shattered Cole's record in the morning session with a time of 28.37, then lowered her own world best with a 28.24 in the final.

"I had pretty high expectations for myself," Konkoly said.

"My goal was to go a 28.6, which would have put me back at first in the world and I thought that was a very aggressive goal.

"I am so happy with my swim."

Konkoly was not the only American breaking records on the second day of action as Alyssa Gialamas and Tucker Dupree followed suit with new American and Pan American records.

London 2012 Paralympian Gialamas touched the wall at 47.47 in the women’s 50m backstroke S5, cutting a full second off her preliminary time in the opening event of the finals.

Dupree closed the last session with a lightning-quick 24.03 in the men’s 50m freestyle S12, improving his 24.20 from the morning.  

He took bronze in the event at London 2012 and is striving to make his third US Paralympic team.

Gialamas was one of three swimmers to leave the pool with multiple first-place finishes after also winning the women’s 50m freestyle S5 in 47.02.

Noga Nir-Kistler topped the podium in the women’s 50m freestyle S6 and 50m butterfly S6 with times of 36.53 and 41.22 respectively, while Lucas McCrory won gold in the men’s 50m butterfly S7 in 35.50 and 50m freestyle S7 in 32.86.

Seventeen-time Paralympic medallist Jessica Long claimed a victory in the women's 100m butterfly S8 in 1:11.75.

US Navy veteran and two-time Paralympic gold medallist Brad Snyder took nearly three seconds off his preliminary time to win the men's 100m butterfly S11 in 1:05.30.

Competition is due to conclude tomorrow with preliminaries and finals in the 150m individual medley, 200m individual medley, 100m freestyle and 100m backstroke.