Olympic champion Adam Peaty went 58.87 in the 100m breaststroke heats as elite competition returned to British waters at the Manchester International Swim Meet.
The eight-time world champion split 27.35/31.52 to qualify for the evening final ahead of James Wilby who stopped the clock at 1:00.99.
It sent Peaty to the top of the fledgling world rankings usurping Nicolo Martinenghi in the process as the only man so far to break 59secs in 2021.
Ellie Challis broke her own British S3 50m backstroke record in 57.52.
The meet at the Manchester Aquatics Centre is the first elite competition in Britain since the the Edinburgh International Swim Meet in March 2020 shortly before the Olympics in Tokyo were postponed in light of the pandemic.
World bronze medallist Luke Greenbank went 1:58.84 in the 200 back, 16-year-old Jacob Whittle clocked the quickest time in the 50 free of 22.96, Dan Jervis went 3:51.7o in the 400 free and James Guy touched in 52.56 in the 100 fly.
Molly Renshaw looked long and smooth in the 200br where she stopped the clock at 2:24.59, Anna Hopkin was fastest through in the 50fr in 24.99 and Georgia Davies sped to 28.52 in the 50 back.
Laura Stephens clocked 2:10.41 in the 200 fly and Holly Hibbott was fastest in the 400 free in 4:10.13.
Finals get under way at 530pm local time with the event livestreamed through the British Swimming YouTube channel.
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