All Team USA members that competed in the pool on Saturday advanced to Saturday night's evening session.
Chase Kalisz, training partner of Michael Phelps who is competing in his first Olympic Games, posted the top time of Saturday’s preliminary heats to enter the 400m individual medley final in first place. He clocked four minutes, 8.12 seconds to finish just ahead of Japan's Daiya Seto, the 2015 World Champion in the event.
Kosuke Hagino, also of Japan, had the third-fastest time of the morning, racing to 4:10.00. American Jay Litherland, who beat out reigning Olympic champion Ryan Lochte at the U.S. Trials in June, is fourth headed into this evening's final with a time of 4:11.10.
In distances longer than 400m, there is no semifinal and the top eight swimmers advance directly to the final from the preliminary heats.
Reigning Olympic champion and new mother, Dana Vollmer, advanced to the semifinals of the 100m butterfly in second with a time of 56.56 second. U.S. teammate Kelsi Worrell also advanced in fourth place, clocking 56.97. Sweden’s Sarah Sjostrom, the reigning world champion and world record holder, posted the fastest time of the morning, 56.26 seconds, to advance to the semifinal in first place.
Also notable in the 100m butterfly heats, Team Refugee athlete Yusra Mardini, a Syrian refugee, won her heat. It wasn’t a fast enough time to advance to the semifinal, but she’ll also swim the 100m freestyle on Wednesday.
Reigning Olympic champion Sun Yang of China went head-to-head with the U.S.' Connor Jaeger in their 400m freestyle heat. Sun raced to 3:44.23, followed by Jaeger in 3:45.37. In the last heat of the event, the U.S. Conor Dwyer battled and defeated Great Britain’s James Guy and Australia’s Mack Horton and David McKeon.
Again, only the top eight advance to Saturday’s final: Dwyer’s time of 3:43.42 (a personal best for him) puts him as the top qualifier. Sun enters in fourth, while Jaeger sits in seventh. 2008 Olympic champion in the event, Park Tae-Hwan of South Korea, missed out.
The U.S.’ Maya DiRado, making her first and decidedly only Olympic appearance, won her 400m individual medley heat in 4:33.50 and advanced to the final in third place. Teammate Elizabeth Beisel, one of this year’s swim team co-captains, raced to 4:34.38 and made the final, too. Beisel owns a silver medal in this event from 2012.
Reigning world champion Katinka Hosszu of Hungary missed the world record by 0.15 seconds, but enters Saturday’s final in first place.
2012 Olympic champion Ye Shiwen of China finished seventh in the heat in a time of 4:45.86 and did not advance to the final. When he won the event in 2012, she raced to an eye-popping 4:28.43.
Great Britain’s Adam Peaty lowered his own 100m breaststroke world record from 57.92 to 57.55 seconds.
The U.S.’ Kevin Cordes and Cody Miller finished second and third, respectively, in their heat behind Japan’s Yasuhiro Koseki. Both Americans advanced into the semifinals, taking place Saturday night.
In the subsequent heats, reigning Olympic champion Cameron van der Bergh of South Africa finished sandwiched between Brazil’s Filipe Franca (in first) and Joao Gomes (third).
To close the session, Australia, the gold medalists from 2012, set a new Olympic record of 3:32.39 and advanced to the women’s 4x100m freestyle final on Saturday. The U.S. squad – made up of Amanda Weir, Lia Neal, Allison Schmitt and Katie Ledecky – raced to 3:33.59 for second place. Ledecky’s anchor leg of 52.64 was nearly a second faster of any of her teammates, likely good enough for her to be on tonight’s relay. Now that she’s competed in the preliminary session, she’s eligible to receive a medal if the U.S. women who swim in the final earn one.