Heung-Min Son earned a penalty and assisted a goal as South Korea beat China 2-0 to finish top of their Asian Cup group.
In his first game since arriving from Tottenham, Son played a starring role as South Korea produced a more confident performance than they did in 1-0 wins over the Philippines and Kyrgyzstan.
Son won the penalty in the 12th minute, his fleet footwork proving too much for Shi Ke to keep up with as the Chinese defender tripped him.
Hwang Ui-jo converted and South Korea scored again in the 51st minute when Son's corner was headed in by Kim Min-jae.
Son could be away for up to five of Tottenham's matches in all competitions if South Korea reach the Asian Cup final on February 1.
South Korea next play in the round of 16 on January 22. If they win, they would then compete in the quarter-finals on January 25 and semi-finals on January 29, before the final.