The Summer Olympic Games will take place in South America for the first time this year, as Rio de Janeiro in Brazil will host the 31st edition of the quadrennial competition.

The countdown to the Aug. 5-21 Rio Games will reach 100 days Wednesday.

The Olympic organizers expect to host 10,500 athletes from 206 countries. Over 17 days, they will take part in 42 sports, including two new additions, golf and rugby.

Rio says 32 competition venues will be spread across four regions of the host city: Deodoro, Maracana, Barra and Copacabana.

South Korea will be competing in its 17th Summer Olympics, and it will be chasing its fourth consecutive top 10 finish in the medal race.

Gracenote, a Dutch sports data analysis firm, projected South Korea to win 12 gold, five silver and 11 bronze medals on its Virtual Medal Table, last updated on April 5.

The gold medal tally would be just one shy of South Korea's all-time record of 13, set in Beijing in 2008 and matched in London in 2012

Three of South Korea's gold medals in 2012 came from archers, and they will once again have to carry the load.

South Korea leads all nations with 19 gold medals since the start of the modern archery competition in 1972. It could complete an unprecedented sweep of all four archery gold medal titles -- men's and women's individual and team events -- in Rio.

Ki Bo-bae, who captured both the women's individual and team gold medals in London, will try to duplicate the feat this year.

She will also try to become the first South Korean female archer to defend an Olympic individual gold medal.

In the shooting range, veteran marksman Jin Jong-oh will try to win a gold at a third consecutive Olympics, something no other South Korean athlete has accomplished.

He won the 50m pistol gold medal at the 2008 Beijing Olympics, and followed that up with gold medals in the 10m air pistol and 50m pistol at the London Games in 2012.

Judokas will be counted on for dominance on the mat. South Korea currently boasts four No. 1-ranked male judokas: Kim Won-jin in 60kg, An Ba-ul in 66kg, An Chang-rim in 73kg and Gwak Dong-han in 90kg.

South Korea has claimed at least one judo gold medal in each of the past three Olympics, and the streak could remain intact thanks to these up-and-comers.

In golf, contested at an Olympics for the first time in 112 years, South Korean LPGA Tour stars, led by world No. 2 Park In-bee, will be strong medal contenders.

The Olympic participants will be determined by the rankings issued on July 11. The top-15 players on the world rankings are eligible, but with a limit of four per country. With its deep talent pool of female golfers, South Korea had eight players inside the top 15 as of Sunday, more than any other nation.

Elsewhere, Lee Dae-hoon in men's taekwondo will be chasing his first Olympic gold. He has won virtually everything a taekwondo fighter can win, with two world titles, two Asian Games gold medals and two Asian championships. He settled for silver in the 58kg event in London. He has since moved up to the 68kg division.

Lee Yong-dae and Yoo Yeon-seong, the No. 1-ranked men's badminton doubles duo, have won their share of international events, and will look to cap it all off with an Olympic gold. Lee won the mixed doubles gold in 2008 and then the men's doubles bronze with a different partner, Chung Jae-sung, in 2012.

In London, South Korea captured two gold, one silver and three bronze medals in fencing, trailing only Italy in the medal count.

Stars from the 2012 Games will be returning, including Kim Ji-yeon, who won the women's individual sabre gold, and Gu Bon-gil, a member of the gold medal-winning men's sabre team.

Conspicuous by their absence in Rio will be gymnast Yang Hak-seon and swimmer Park Tae-hwan.

Yang, the 2012 Olympic champion in men's vault, underwent surgery in March to repair a ruptured Achilles tendon, and his rehab is expected to take three to four months. While Yang himself has said he hasn't given up on his Olympic dreams, he may not have enough time to train even if his cast comes off before the Rio Games.

Park, a four-time Olympic medalist in freestyle, including the 400m gold in 2008, has been ruled ineligible for Rio because of his doping history.

Park served an 18-month suspension after testing positive for testosterone. His ban ended in March, but under a Korean Olympic Committee rule, athletes who have served doping suspensions can't represent the country for three years, starting on the day their ban ends.

The KOC has defied public pressure to amend the rule and said it would not make a special exception for a particular athlete. (Yonhap)