Katie Ledecky faces a task seemingly tailor-made to accentuate her freestyle swimming greatness on Day 4 of action from the Tokyo Aquatics Center.
In the span of a little over an hour, Ledecky will race the finals of both the women's 200m freestyle and women's 1500m freestyle. The latter of which is taking place for the first time as an Olympic event.
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Others in action include Caeleb Dressel in the semifinals of the men's 100m freestyle and Kristof Milak in his signature men's 200m butterfly.
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.
Men's 100m Freestyle - Semifinals
Dressel is the favorite in the event but took an unexpected, albeit largely insignificant, loss in his preliminary heat.
Dressel races in the first semifinal alongside sixteen-year-old Romanian phenom David Popovici.
Italy's Thomas Ceccon, who won Dressel's heat, is up second along with American Zach Apple.
Women's 200m Freestyle - Final
Can Ariarne Titmus go 2-0 against Ledecky at the Tokyo Olympics? The pair are matched up again following Titmus' win in the 400m freestyle on Day 3.
Although Ledecky is the defending Olympic champion in this event, it is generally considered her weakest of the freestyles in which she competes.
Titmus goes in as the favorite, though neither Ledecky nor Hong Kong swimmer Siobhan Haughey are to be counted out in what is expected to be a fast and highly competitive race.
Men's 200m butterfly - Final
Milak, of Hungary, is the new face of the event Michael Phelps dominated for the better part of two decades.
The race for the gold medal should be academic for Milak, who could have sights set on lowering his own world record of 1:50.73.
Gunnar Bentz represents Team USA as the lone American in the final, which also includes longtime Phelps rival Chad Le Clos of South Africa.
Women's 200m butterfly - semfinals
Americans Regan Smith and Hali Flickinger race side-by-side in the first semifinal with both likely to advance to the final.
Chinese swimmers Zhang Yufei and Yu Liyan will attempt to do the same in semifinal No. 2.
Men's 200m breaststroke - semifinals
Nic Fink aims to join favorites Zac Stubblety-Cook and Arno Kamminga in the final of the 200 breast.
Anton Chupkov, the 2016 gold medalist, will look to set himself up for an Olympic repeat.
Women's 200m IM - final
This one could come down to the two Americans, Alex Walsh and Kate Douglass, who both qualified among the top swimmers out of the semifinals.
400m IM gold medalist Ohashi Yui of Japan, along with 2016 gold medalist Katinka Hosszu of Hungary are factors as well.
Women's 1500m freestyle - final
Prepare for 15 minutes of smooth, emphatic dominance as Ledecky races her strongest event.
At world championships and U.S. Trials, Ledecky has demonstrated that she can still crush the field in the 1500 by several seconds even after competing in the 200 free in the same night.
The race for silver could come town to the other American in the race, Erica Sullivan, against Chinese distance specialist Wang Jianjiahe.
Men's 4x200m Freestyle - final
Great Britain and Australia are the favorites in the 800 relay as the United States clings to an outside shot at a medal.