INDIANAPOLIS, Indiana – Just one day after setting a world record in the 1500-meter freestyle, Olympic gold medalist Katie Ledecky (Bethesda, Md./Stanford Swimming) was at it again Thursday with a U.S. Open record in the 400m free on day two of the TYR Pro Swim Series at Indianapolis at the Indiana University Natatorium.

Ledecky touched in 3 minutes, 57.94 seconds, good for the second-fastest swim of all-time in the event, trailing only her gold-medal performance at the 2016 Olympic Games. Later in the session, she was fifth in the 100m free in 54.56.

“I had two really great swims. I was just trying to make a few improvements off of this morning’s swims, just pacing and being a little more controlled,” Ledecky said. “I still had a little too high of a tempo in the first 50 of my 400, but overall I was really pleased with the swim, the time.”

TYR Pro Swim Series men’s leader Zane Grothe (Boulder City, Nev./Mission Viejo Nadadores) matched Ledecky with his second win in Indianapolis in the men’s 400m free in 3:48.79. He also took the men’s 1500m free title on Wednesday.

Other U.S. Olympians touching first Thursday included Nathan Adrian (Bremerton, Wash./California Aquatics) in the men’s 100m free in 48.69, Kelsi Dahlia (Westampton, N.J./Cardinal Aquatics) in the women’s 100m fly in 57.38, Gunnar Bentz (Atlanta, Ga./Dynamo Swim Club) in the men’s 100m fly in 53.03 and Melanie Margalis (Clearwater, Fla./St. Petersburg Aquatics) in the women’s 200m breast in 2:24.62.

National Junior Team member Daniel Roy (Spokane, Wash./Unattached) took the victory in the men’s 200m breast in 2:09.73, and Canadian Olympian Taylor Ruck won the women’s 100m free in 53.42.

Winning the 200m mixed medley relay was the Krayzelburg squad of Matt Grevers (Lake Forest, Ill./Tucson Ford Dealers Aquatics), Nic Fink (Morristown, N.J./Athens Bulldog Swim Club), Dahlia and Olivia Smoliga (Glenview, Ill./Athens Bulldog Swim Club) in 1:43.35.

The four-day meet continues through Saturday with 10 a.m. EDT prelims followed by nightly finals at 7 p.m. EDT.

Coverage of each finals sessions will be available on various NBC Sports platforms, including live coverage on NBC Sports Network on Saturday at 7 p.m. EDT. Friday’s finals will air live on the Olympic Channel at 7 p.m. EDT. Friday’s finals session also will re-air Sunday on NBC Sports Network at 7 p.m. EDT. A live webcast of daily prelims is available at usaswimming.org.

Complete results from the TYR Pro Swim Series at Indianapolis are available here: http://www.omegatiming.com/Competition?id=0001120101FFFFFFFFFFFFFFFFFFFFFF&sport=AQ&year=2018

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