Los Angeles: Multi-Olympic champion Michael Phelps powered to victory in the 100 metres butterfly to win his 50th United States national swimming title on Thursday.
Phelps` time of 50.65 seconds was the fastest in the world this year and was too much for the field, with Tyler McGill in second in 52.20 and Tim Phillips third in 52.41.
"I`m fairly pleased with that," Phelps said after the race. "That`s pretty good for right now. That`s the best I`ve felt."
Phelps said he felt "absolutely awful" after winning the 200 metres butterfly and freestyle on Wednesday to claim a record 49th U.S. title and move past Tracy Caulkins.
Phelps, the winner of eight gold medals at the Beijing Olympics, will also contest the 200 metres individual medley and the 200 metres backstroke at the championships, which conclude on Saturday.
World champion Rebecca Soni finished strongly to win the women`s 100 metres breaststroke ahead of world record holder Jessica Hardy in the fastest time this year.
"That last 50 metres is really my forte. I felt great coming home," Soni said of her one minute, 5.73 seconds effort.
Kara Lyn Joyce, the second fastest American woman this year at the distance, won the 50 metres freestyle in 24.86 seconds.
"I had my eyes closed, most of the race," she said. "I had no idea where I was. I was just hoping for something."
The men`s 50 was won by Nathan Adrian in 21.7 seconds, the second fastest time in the world this year.