Paik opened scoring for South Korea in the 31st minute when he headed down a free kick from Lee Jin-hyun. Saudi Arabia leveled the score just a minute after the second-half kickoff, but Lim Min-hyeok gave the lead back to the hosts in the 60th. Lee Sang-heon further punished the visitors a minute later as he found the back of the net after receiving Paik's pass.

This was the first tune-up match since head coach Shin Tae-yong confirmed his 21-man squad for the World Cup last month.

"I'm satisfied with the players' movements, tempo of the game, and goal scoring," Shin said after the match. "We also tried some set pieces that we're going to use at the World Cup and I think they worked well."

Shin's side will have two more friendly matches before entering the U-20 World Cup. South Korea will take on Uruguay on Thursday in Cheongju, North Chungcheong Province, and face Senegal three days later in Goyang, Gyeonggi Province. Both Uruguay and Senegal are also participants of the U-20 World Cup.

"We're in the process of building the team," he said. "We will complete the perfect formation after playing two remaining friendly matches."

Shin admitted South Korea's defense was not perfect against Saudi Arabia, but vowed to fix the problem.

"Our defensive line should be prepared from behind, but we showed some shaky moments maybe because the players were careless about it," he said. "We will test both the back three and the back four (formations) to make our defense stronger."

South Korea will host the FIFA U-20 World Cup from May 20 to June 11 in six local cities. The young Taeguk Warriors are in Group A with Argentina, England and Guinea at the 24-team tournament. (Yonhap)