INDIANAPOLIS -- Rachel Bootsma won the 50-meter backstroke in 27.68 seconds Thursday night in the USA Swimming National Championships to break the American and U.S. Open records, and Kevin Steel and David Plummer also set U.S. Open records.
Steel broke the 50 breaststroke mark that he set in the preliminaries, finishing in 27.26 seconds. Plummer won the 50 backstroke in a record 24.52.
With the victories, they qualified for the world championships in Barcelona, Spain, in late July.
"I really just tried to focus on my start and get off the block," Bootsma said. "There are still some improvements I can make, but it's my first time setting a record, so I'm really excited."
Four-time gold medalist Missy Franklin -- who already qualified in the 100 freestyle, 200 freestyle and 200 backstroke -- was second in 27.98.
Steel edged Arizona club teammate Kevin Cordes.
In the 400 individual medley, Maya Dirado won in a career-best 4:34.34. Dirado said her strong performances in the 200 butterfly and freestyle earlier in the week gave her a confidence boost going into the race.
"The 400 IM is what I think about every day at practice," Dirado said. "I was just really excited to do a race that I truly prepared for and had thought about a lot."
Nineteen-year-old Chase Kalisz won the men's race in 4:11.83.
Olympic star Ryan Lochte normally dominates the 400 IM, but he scratched before the race. Kalisz said that even though Lochte scratched, he'd like to think he didn't get the win by default.
"I want to feel like I earned the spot," Kalisz said. "Obviously, it opened up a good position for me, and it's good for him. He swam a great 100 fly, but obviously I'd like to race him."
World record-holder Dana Vollmer continued to dominate the 100 butterfly, winning in 57.53.
After competing in the Olympics, Vollmer said she debated taking the fall off to consider retirement, but after she started to attend morning workouts again she got the itch to compete.
"Each day of training has really made a difference for me," Vollmer said. "I just wanted to get up there -- regardless of the time -- make the team, and now I have another month to train going into world championships."
Eugene Godsoe won the 100 butterfly in 51.66. Lochte was second in 51.71.
Lochte said he is a closer and prefers to swim a 200-meter race to a 100-meter event, but is going to be training more in the 100 butterfly.
"I just have to believe in my training," Lochte said. "I've trained really hard these past two months. It wasn't close, but I have to hand it to everyone. They did really good."
World record-holder Jessica Hardy won the 50 breaststroke in 30.24 in the first year the event is being contested at the national championships.