Caeleb Dressel, the top star in men's swimming, has had a relatively muted roll in the proceedings in the pool thus far in Tokyo. That changes on Day 6.
Dressel will swim the most classic of Olympic races, the 100m freestyle. He is the world champion and world record holder in the event.
Elsewhere, Katie Ledecky and Ariarne Titmus match up for the third time at the Tokyo Games, but this time they've got their entire teams behind them in the 4x200m freestyle relay.
Watch the action LIVE in primetime on NBC beginning at 9:30 p.m. ET and stream the entire session LIVE on NBCOlympics.com and the NBC Sports app.
Follow along below for live updates, results and highlights as things unfold.
Men's 800m Freestyle, Final
Bobby Fink came out of absolutely nowhere.
The lone American in the men's 800m freestyle won the event's Olympic debut in 7:41.87.
At the 750 meter mark, he was not in the picture for a medal, let alone gold. But a monumental final length of the pool saw him surge past Gregorio Paltrinieri (ITA), Mykhailo Romanchuk (UKR) and Florian Wellbrock (GER) to be first to the wall.
"I just really wanted to get my hand on the wall," Finke said. "I was able to switch into another gear."
Men's 200m Breaststroke, Final
Aussie Zac Stubblety-Cook mounted a massive late charge to win his first Olympic gold medal in 2:06.38.
Stubblety-Cook trailed Dutch swimmer Arno Kamminga by over a second at the 150 mark but closed in 32.21 to touch first.
Kamminga took silver, ahead of Matti Mattsson of Finland for bronze.
American Nic Fink finished fifth.
Women's 100m Freestyle, Semifinals
Emma McKeon of Australia leads a field filled with former Olympic champions. McKeon set an Olympic record in the preliminary heats, and while she did not lower that record in the second semifinal, she qualified first in 52.32.
Within a second of her time though, you'll find Australia's Cate Campbell, Sweden's Sarah Sjostrom and Canada's Penny Oleksiak.
That's 15 combined Olympic medals headed to a star-studded final.
That final will also include American Abbey Weitzeil, who qualified seventh in 52.99.
Men's 200m backstroke, Semifinal
Both Americans Bryce Mefford and defending gold medalist Ryan Murphy are safely into the final.
Neither won their second semifinal, though, which went to Great Britain's Luke Greenbank.
Russian athlete Evgeniy Rylov, the 100 back gold medalist in Tokyo, was the only swimmer to break 1:56, winning the first semi in 1:54.45.
Women's 200m butterfly, Final
Americans Hali Flickinger and Regan Smith are both in the mix for the gold medal, though China's Zhang Yufei is surely the favorite after breaking 2:05 in the semifinal round.
2019 world champion Boglarka Kapas of Hungary is also very much in the podium picture.
Men's 100m freestyle, Final
After ceding the stage for the first half of the Tokyo swimming competition, its time for Caeleb Dressel to have his moment.
It won't be easy though, as Dressel, the defending world champion and world record holder in the 100 free, has Russian athlete Kliment Kolesnikov to deal with.
Kolesnikov qualified with a better time out of the semifinals, though Dressel hinted after his heat that there was a much faster time waiting for the final.
Women's 200m breaststroke, Semifinal
South Africa's Tatjana Schoenmaker came within .05 of the world record in the heats with a blistering time of 2:19.16. Can she lower that in the semifinal?
Americans Lilly King and Annie Lazor should comfortably advance to the final as well.
Men's 200m IM, Semifinal
How low will Michael Andrew go? The versatile short-distance racer appears to be in control of proceedings in the 200 IM.
Chase Kalisz, the 400 IM gold medalist earlier in the week, will expect to make the final along with Japan's Hagino Kosuke, the defending gold medalist.
Women's 4x200m freestyle, Final
Australia nearly broke the world record with Ariarne Titmus sitting on the bench. Throw the individual 200m freestyle gold medalist into the mix and this one should go the Aussies' way comfortably.
The United States may give them a serious run, though, with seasoned veterans Allison Schmidtt leading off and Katie Ledecky anchoring.