South Korea has secured at least a bronze medal in the women's doubles badminton event at the Tokyo Olympics, after two pairs advanced to the semifinals on the opposite sides of the bracket on Thursday.

Kim So-yeong and Kong Hee-yong defeated Mayu Matsumoto and Wakana Nagahara of Japan 2-1 (21-14, 14-21, 28-26) in the quarterfinals at Musashino Forest Sport Plaza. Hours later, Lee So-hee and Shin Seung-chan beat Selena Piek and Cheryl Seinen of the Netherlands 2-0 (21-8, 21-17) in the quarters as well.

Lee and Shin will face the Indonesian tandem of Greysia Polii and Aprlyani Rahayu in the semifinals Saturday. Kim and Kong will play Chen Qingchen and Jia Yifan of China in their semifinals match.

Because the two Korean teams are on different sides of the bracket, they can only meet in the gold medal match or the bronze medal match.

The gold medal and bronze medal matches are scheduled for next Monday.

Kim and Kong, ranked fifth in the world, battled the second-ranked Japanese pair hard for three games.

In the first game, the South Koreans led by as much as 11-2. Matsumoto and Nagahara cut it to 15-10 at one point but couldn't overcome the deficit.

The Japanese returned the favor in the second game, scoring the first four points en route to a 21-14 win.

Kim and Kong trailed for most of the third game, and the Japanese held the match point at 20-19.

The South Koreans forced deuce, and at 26-26, they scored the final two points to close out the win.

Kim and Kong said they had to lean on each other when they were pushed to the brink of defeat.

"I was wobbly toward the end of the third game. But So-yeong kept trying to calm me down," Kong said. "I was able to hold myself together."

Kim chimed in: "I wanted to trust my partner and leave it all on the court. I am just so happy we got the win."

Lee and Shin had a much easier time in their quarters. They won the first game 21-8 in just 16 minutes. They had a 16-8 lead in the second game, and held off the Dutch team for a 41-minute victory.

Lee and Shin said they won't be satisfied with anything less than gold.

"We're really happy to make it to the semifinals but we're going to have to bear down and concentrate on the next match," Lee said. "We'll try to reach even greater heights."

Shin said, as nice as it is to have grabbed at least a bronze, "We will not let our guard down against Kim So-yeong and Kong Hee-yong."

South Korea hasn't won gold in the women's doubles since Chung So-young and Hwang Hye-young won the inaugural title in 1992. (Yonhap)