In Friday's semifinals, they will go on to face Lim Jong-hoon and Yang Ha-eun of South Korea. Lim and Yang knocked out Lubomir Pistej and Barbora Balazova of Slovakia 3-0 (11-6, 11-7, 12-10) in their quarterfinals match.

Against the 2018 world champions, Jang and Cha battled back from a 10-9 deficit in the opening game to score three straight points.

After dropping the next game, Jang and Cha bounced back for a breezy 11-5 win in the third game. The Japanese duo extended the match by taking the fourth game 11-9.

And in the deciding fifth game, Jang and Cha opened up an 8-4 lead, and closed out the Japanese 11-5.

Jang said Cha did most of the damage in their victory.

"She played even better than I'd expected, and I was pleased to win this one for our fans," Jang said. "We'll try to keep this up and accomplish our goal of winning the gold medal here."

Watching from the sidelines, former South Korean men's coach Kim Taek-soo said Jang and Cha complement each other well.

The right-handed Jang is an aggressive player who can be error-prone at times. Cha, who hits left-handed, is the steadier player of the two.

Kim said he felt the unified Korean team should have taken the match 3-0.

"Woo-jin looked quite nervous early in the match, but Hyo-sim backed him up nicely," Kim observed. "Thanks to her steady presence, Woo-jin was able to cut down on his errors and be the attacking force that he normally is."

The second South Korean pair in the tournament, Lee Sang-su and Jeon Ji-hee, lost their quarterfinals match. Masataka Morizono and Mima Ito prevailed over the South Koreans 3-1 (9-11, 11-7, 11-9, 12-10).

This competition is open to the top 16 players in the men's and women's singles, and the top eight teams in the men's, women's and mixed doubles, based on their performances in the 12 ITTF World Tour events. (Yonhap)