Korea Republic began it's FIFA U20 World Cup campaign with a 2-0 win over Mali in Bogota.
Lee again proved to be the South Korean side's best threat with a curling free-kick on 12 minutes, but this time his effort narrowly sailed over the crossbar.
Five minutes after the restart, Kim Kyung Jung caught the end of a long-range throw-in from Rim Chang Woo inside the area, and tapped his effort home from five metres out.
Mali searched for an equaliser, but missed chances from Malle and Diarra cruelled the West African side.
When Baek Sung Dong was fouled in the area in the 80th minute, Jang Hyun Soo made no mistake from the spot.