South Korea's Yoo Eun-chong, right, returns the ball as her partner North Korea's Choe Il looks on during their preliminary round match against Spain's Alvaro Robles and Galia Dvorak at the International Table Tennis Federation World Tour Platinum Korea Open in Daejeon on July 17, 2018. AFP-Yonhap

A unified Korean mixed doubles team will take on a South Korean tandem at an international table tennis competition here this week.

Choe Il (North Korea) and Yoo Eun-chong (South Korea) will play the third-seeded South Korean duo of Lee Sang-su and Jeon Ji-hee in Thursday's round of 16 match at the International Table Tennis Federation (ITTF) World Tour Platinum Korea Open in Daejeon, 160 kilometers south of Seoul.

Choe and Yoo defeated Alvaro Robles and Galia Dvorak of Spain 3-2 (8-11, 11-9, 8-11, 11-9, 13-11) in a qualification match Tuesday. But they will face an uphill battle against Lee-Jeon, considered the top South Korean pair that has a chance to contend for gold at the Asian Games in August.

North Korea's Choe Il, right, and his partner South Korea's Yoo Eun-chong celebrate their victory against Spain's Alvaro Robles and Galia Dvorak during their preliminary round match at the International Table Tennis Federation World Tour Platinum Korea Open in Daejeon on July 17, 2018. AFP-Yonhap

The Choe-Yoo team is one of four joint Korean pairs competing at the Korea Open.

Also in the round of 16, another unified mixed doubles team, Jang Woo-jin (South Korea) and Cha Hyo-sim (North Korea), will take on the second-seeded team from Hong Kong, Wong Chun Ting and Doo Hoi Kem.

Jang and Cha booked a spot in the round of 16 after their Mongolian opponents, Battumur Baatar and Delgermaa Mergen, withdrew from their qualification match Tuesday.

South Korean supporters for the united Korea team wave "Unification flags" as they watch the preliminary round of the International Table Tennis Federation World Tour Platinum Korea Open in Daejeon on July 17, 2018. AFP-Yonhap

The Koreas have a unified team each in the men's and women's doubles, whose round of 16 action will also begin Thursday.

On the men's side, the fifth seed Lee Sang-su (South) and Pak Sin-hyok (North) have teamed up. Suh Hyo-won (South) and Kim Song-i (North) will play together in the women's event.

The tournament runs through Sunday. (Yonhap)