Lilly King set an American record in the 50-meter breaststroke Thursday at the US Swim Championships in Indianapolis, a qualifying meet for next month's World Championships in Budapest, Hungary. King won the final in 29.66 seconds, beating runner-up Katie Meili by 0.45 of a second and breaking the old US mark of 29.80 set by Jessica Hardy in 2009.
Three other sprint races produced meet records for winners who booked their trips to worlds. Justin Ress won the 50 backstroke in 24.41, .11 under David Plummer's old meet mark from 2013. Kevin Cordes, coming off a 200 breaststroke title Wednesday, won the 50 breast in 26.88, shaving .01 off the meet record he set in preliminaries. Hannah Stevens won the 50 back in 27.63, .05 under Rachel Bootsma's mark from 2013.
Caeleb Dressel, who already won the 50 butterfly crown, captured the 100 fly title in 50.87, .43 ahead of Tim Phillips. Kelsi Worrell, also coming off a 50 fly title, won the 100 fly crown in 57.38 with Sarah Gibson second, .58 adrift. Chase Kalisz, last year's Rio Olympic runner-up in the 400 individual medley, took the US crown in the event in 4:06.99 with fellow Olympian Jay Litherland second in 4:09.31.
Leah Smith set a personal best in the women's 400 IM to win in 4:33.86 with Elizabeth Beisel second in 4:38.55. Five-time Olympic champion Katie Ledecky, who was idle Thursday, has already won the 200 and 800 freestyle titles and seeks her third US crown Friday in the 400 free. She goes for the 1,500 free title on Saturday.
Ledecky captured 200, 400 and 800 free Olympic gold last year in Rio - defending the 800 crown she won in London - and helped the US women's 4x200 relay win as well. Ledecky won the world 400, 800 and 1,500 freestyle titles and shared in a 4x200 free relay win in 2013 in Barcelona then defended those crowns while adding the 200 world title in 2015 at Russia.