-- RIO DE JANIERIO -- There will be more than 11,000 athletes from more than 200 countries and territories competing in the Olympics that begin Friday. That means endless great stories and Olympians to follow, but here are our 10 top athletes and events to watch.
The fastest man in the world has won gold in the 100, 200 and 4x100 relay in the past two Olympics, but Bolt hurt his hamstring at the Jamaican Olympic trials. Does that mean he won't be performing his signature lightning bolt salute in Rio? Maybe. Americans Justin Gatlin and Trayvon Bromell have the fastest times in the 100 this year (9.80 and 9.84, respectively), with Bolt holding the fourth-best, at 9.88. He's still the man to beat, though. As Gatlin said, "He's Usain."
Despite temporarily retiring after London 2012, Phelps is back and racing in his fifth Olympics (his first was Sydney in 2000 at age 15). He's 31 and a father now, but expect him to add a couple more medals to his Fort Knox-like collection of gold. Look for other (and younger) Americans, especially Katie Ledecky, to have top performances as well.
The 19-year-old is a three-time world all-around champion and a four-time U.S. national all-around champ, and she will be aiming to continue America's streak of Olympic women all-around champions (Gabby Douglas in 2012, Nastia Liukin in 2008 and Carly Patterson in 2004). Bet on Biles to win the all-around -- she hasn't lost that competition in three years -- and possibly five gold medals overall.
Decathlon world record-holder Ashton Eaton won gold in London and is heavily favored to become the third decathlete to win two consecutive Olympic titles (Daley Thompson did so in 1980 and 1984 and Bob Mathias in 1948 and 1952). He also will be rooting for his wife, Canada's Brianne Theisen-Eaton, to win the heptathlon. They will officially become "The World's Greatest Married Athletes."
Many Olympic sports can get serious, but beach volleyball is always fun, and it is extremely popular in Brazil. After winning gold with Misty May-Treanor at the 2004, 2008 and 2012 Olympics, Kerri Walsh Jennings will go for her fourth with new Olympic partner April Ross. They will face stiff competition from Brazilians Larissa Franca and Talita Antunes. Regardless of who wins, with the music blaring, dancers twisting and fans going wild on Copacabana Beach, this will be one of the most entertaining and fun events of these Games.
Refugee Olympic Team
Don't focus only on gold. There are 10 Olympians who fled Syria, South Sudan, the Democratic Republic of Congo and Ethiopia for safety and freedom. They will be competing as the Refugee Olympic Team, and they all have fascinating stories. Consider swimmer Yusra Mardini. Her family left Syria when her home was destroyed. At one point during her escape to Europe, Mardini and others had to dive into the sea and swim while helping pull their dinghy to an island. "I had one hand with the rope attached to the boat as I moved my two legs and one arm," she told a reporter. "It was three-and-a-half hours in cold water. Your body is almost, like ... done."
No, LeBron James and Steph Curry won't be playing, but Kevin Durant, Diana Taurasi and other stars will, and the U.S. men's and women's basketball teams remain the heavy favorites to win gold. The women's side has won the past five gold medals and 41 consecutive games heading into Rio.
More than 100 Russians have been banned from these Olympics because of doping, with the track and field, rowing and weightlifting teams barred from competition. Still, there will be close to 300 Russian athletes. Will they be booed for the suspicions or cheered for still being here? How many will win? Of those who do, how many will have their medals stripped later, after doping tests?
The U.S. women's team won the World Cup last year and will be going for its fifth Olympic gold in six attempts. The Americans' only non-gold tournament was in Sydney 2000, and they are the favorites here. But don't count out star Marta and host Brazil.
Rugby is returning to the Olympics for the first time since 1924, when the U.S. (yes, the U.S.!) won gold. The Americans aren't expected to win this summer, but then again, they weren't expected to win in 1924. Among the top contenders to win is Fiji, which has never won an Olympic medal in any event.