Swimming returns to NBC’s primetime coverage of the Olympic Games with the first of eight straight days of finals Saturday. Coverage begins at 9:30 p.m. ET, carrying the action LIVE from the Tokyo Aquatics Center in Japan. In addition to the NBC broadcast, complete coverage is also streaming LIVE on NBCOlympics.com and the NBC Sports app.
The first four sets of swimming medals are on the line in the men’s 400m individual medley, men’s 400m freestyle, women’s 400m IM and women’s 4x100m relay. Two sets of semifinals round out the schedule on Day 2 of the Tokyo Games.
Chase Kalisz, Jay Litherland, Emma Weyant and the first American relay team aim for Team USA's first swimming medals of the Tokyo Olympics.
Follow along here for live updates from each event, including start lists, results and highlights and results from each of the night's finals.
Men's 400m IM - Final
The United States is off an running in the best possible way.
The Americans swept gold and sliver, with Chase Kalisz, the Rio 2016 silver medalist, executing arguably the best race of his career to clinch gold and Jay Litherland closing hard in the final 50 meters to complete the 1-2 finish.
Kalisz turned at the 300-mark nearly 2.5 seconds ahead of top-seeded Kiwi Lewis Clareburt, who usually closes well. On commentary at that moment, Michael Phelps, a longtime friend and former training partner of Kalisz's, called it "The closest 400 IM I think I've ever seen."
But that comment would prove to be premature, as Kalisz won by over three-quarters of a second.
"It mean's the word," Kalisz said through the pain of lactic acid buildup. "This was the last thing I really wanted to accomplish in my swimming career. This is something that's been a dream of mine for as long as I can remember."
Litherland, who was born in Osaka, Japan, was behind significantly heading into the final 50, but closed exceptionally well to take silver
Women's 100m butterfly - semifinals
Men's 400m freestyle - Final
Tunisia's Ahmed Hafnaoui shocked the Tokyo Aquatic Center, winning the men's 400 free from Lane 8 in 3:43.36.
Australia's Jack McLoughlin took silver, while American Kieran Smith took bronze.
Women's 400m IM - Final
Japan has is first swimming gold medal of the Tokyo Games. Ohashi Yui could not be caught despite charging efforts from both Americans in the pool. Ohashi finished in 4:32.08.
Emma Weyant took silver in 4:32.76 and Hali Flickinger completed the podium over two seconds later for Team USA's fifth medal of the evening.
Mireia Belmonte (ESP) and Katinka Hosszu (HUN) with eight Olympic medals between them, finished off the podium in fourth and fifth, respectively.
Men's 100m backstroke - semifinals
Great Britain's dominant breaststroker Adam Peaty set a predictably quick pace, advancing as the top seed by a half-second.
Both Americans in the event, Michael Andrew and Andrew Wilson, advanced to the final.
Women's 4x100m Freestyle relay - final