THE GYMNASTS TAKE THE FLOOR
Gabby Douglas, Aly Raisman and the other American gymnasts will be competing on all of the apparatuses, from balance beam to uneven bars, to qualify for the finals in team, all-around and event competition. The top eight teams will advance to the finals, and the U.S. Olympic women are the favorites to take team gold medal.
Douglas didn’t have a great performance at the Olympic Trials, but the reigning all-around gold medalist is hoping to bounce back and lead the team to a second team gold in a row.
Sunday is also a chance to see Simone Biles in the Olympic arena for the first time. She’s won three straight all-around world championships and four U.S. gymnastics titles in a row, too, so it would be safe to say expectations are high.
How to Watch: See the women begin the qualifying round as they try to defend their gold medal here on your smartphone or desktop computer, or on NBC Sports, at 4:30 p.m. ET.
LEDECKY GOES SOLO
Swimmer Katie Ledecky has advanced to the 400m freestyle final on Sunday evening, setting a new Olympic record during her qualification heat with a time of 3:58.71.
Ledecky, 19, made a big splash four years ago in London. She is competing in five events this summer: the 200-meter, 400-meter and 800-meter freestyle along with the 4x200-meter free relay to go with Saturday’s race.
She'll be seeking the first of an expected three individual gold medals, going in as a heavy favorite in the 400 freestyle. The only suspense now seems to be whether she'll break her own world record.
She went into the Olympics with the world record in 400-meter freestyle, so she’ll have one eye on her opponents in the pool and one on the clock when she dives in for the high-octane event.
How to Watch: Keep up with Ledecky’s quest for gold in Rio from the Aquatics Center here on your smartphone or desktop computer, or on NBC at 12 p.m. ET for the preliminary heats. If she advances, the final will be at 9 p.m. ET.
If any sport says "Rio," it’s beach volleyball at Copacabana, and on Day 2 of the games American newcomers Lauren Fendrick and Brooke Sweat battled for a win Sunday in the Olympic sand. On the men’s side, Phil Dalhausser returns to Olympic sand with his partner from the past, Nick Lucena.
The year 2013 was big for Sweat. She won her first domestic volleyball tournament that year, then teamed up with Kendrick, who won the title in 2011. Fendrick and Sweat, both Olympic rookies, won their first set 21-14. But Poland's Kinga Kolosinska and Monika Brzostek rallied back to take the second, 21-13. They dominated the third set 15-7 for the win.
Dalhausser already has one gold medal, from the 2008 games in Beijing, but didn’t medal in London in 2012. Now paired up with Lucena, he’s got a good chance at a second medal, since the duo ranked third going into the Olympics in June.
How to Watch: Watch the women at 10 a.m. ET here on your smartphone or on your desktop computer, or click here to watch the men at 3:30 p.m. ET. Both matches will air on NBC.
CAN MASSIALAS BE FOILED?
Alexander Massialas, a 22-year-old Stanford student, was the youngest American male athlete at the London Games four years ago, but wants to set a much more important record this time around.
Team USA has never won a gold medal in individual foil fencing, but Massialas is the world No. 1, and is looking to change that Sunday. Coached by his dad, he gives the U.S. it’s best-ever shot at taking gold in a sport that dates back to the first Olympic games in Athens in 1896.
How to Watch: Fencing begins at 3 p.m. ET. Watch it here on your smartphone or desktop computer, or on MSNBC.
BRAZIL’S SOCCER DROUGHT
Soccer is Brazil’s national sport, but their soccer team wasn’t able to score in their opening game Thursday, a scoreless draw against South Africa, even though South Africa ended the match down a man.
Led by stars Neymar (you may recognize him from his world-famous team, FC Barcelona) and Gabriel Jesus, the "Selecao," as they’re known in Rio, will be roaring back onto the pitch with a match against Iraq. They have a point to prove in this competition — Brazil hosted the World Cup two years ago, and the national team wasn’t able to win on home turf.
How to Watch: The opening whistle is at 9 p.m. ET. You can watch the game here on your smartphone or desktop computer, or on NBC Sports.
DIVER’S QUEST FOR 5 RECORDS
The sport of diving is a matter of centimeters — it’s incredibly difficult to pull off a perfect dive.
But China’s Wu Minxia has a different kind of perfection in mind, and it starts with women’s synchronized 3-meter springboard on Sunday. She could set five records on Sunday, including most Olympic diving gold medals by an individual — she’s tied with five other divers at the moment, including American star of the 1984 and '88 games, Greg Louganis.
"I am looking forward to perfection on my competition day," Wu told the South China Morning Post last week.
How to Watch: See the diving action here on your smartphone or desktop computer beginning at 3 p.m. ET.