Olympic silver medallist Michael Jamieson secured qualification for the Commonwealth Games by winning the 200m breaststroke title at the British Championships in Glasgow.
The 25-year-old Scot won in two minutes 7.79 seconds, the fastest time in the world this year.
Adam Peaty and Andrew Willis finished second and third, also securing qualification for the Commonwealths.
James Guy broke the British 400m freestyle record to win his event.
England's Siobhan-Marie O'Connor and Aimee Willmott also qualified for the Commonwealth Games, which will take place in Glasgow between 23 July and 3 August, by winning the 200m freestyle and 400m individual medley respectively.
Jamieson suffered a health scare late last year after developing an irregular heartbeat in training.
He returned to action soon after and posted the previous quickest time in the world this year just last week
"I'm pretty happy with that swim, so it's job done in terms of qualifying for the Commonwealths," he said.
Englishman Peaty, who took a surprise second in 2:09:40, added: "I didn't expect to swim that quickly, but it was the perfect race for me."
Guy's time of 3:45.15 beat the mark of two-time Olympic medallist David Davies by 0.09 secs.
"He was a massive inspiration to me and one of my heroes," Guy told BBC Sport.
Distance specialist Jazmin Carlin, 23, finished second in the 200m freestyle final and will compete in the event for Wales later this summer having been pre-selected for the Commonwealth Games team after competing for Great Britain at last year's World Championships.
"Being pre-selected really takes the pressure off," Carlin, who won three British titles in 2013, told BBC Sport. "I'm so tired coming into this, but it's good to be challenged and I'm confident about winning medals this summer."
Countryman Ryan West, 16, who has cerebral palsy, all but secured his place at the Commonwealths after recording a time of 1:00.05 in the S9 100m freestyle multi-classification event.
Matthew Wylie won in another British record of 58.69secs.