Sunday's events promised a return to grandeur.

With some of the Games' most prominent athletes taking center stage—Naomi Osaka, Simone Biles, Simone Manuel and players on the U.S. men's basketball team among them—and newly added sports like skateboarding and surfing on the menu as well, thrills were expected.

Mostly, the slate delivered, though there were some surprisingly underwhelming moments. It's all part of the Olympic experience.

Here's a quick recap of Day 2's roller-coaster ride.

Winner: Team USA in the Swimming Pool

Team USA has won the most total medals in each of the last six Summer Olympics, and swimming has been the biggest reason for that dominance.