South Korea earned their second win of the Asian Football Confederation Under-23 Championship ©Getty Images

South Korea earned their second win of the Asian Football Confederation Under-23 Championship in Thailand to top their group in a competition where places at this year's Olympic Games in Tokyo are on the line. 

The South Korean side had first edged past China, today recording another narrow victory against Iran at Tinsulanon Stadium in Songkhla.

Lee Dong-jun scored first for South Korea in the 22nd minute, before Cho Kyu-seong made it 2-0 just over 10 minutes later. 

Despite the comfortable first-half, an Iranian goal from Reza Shekari in the 54th minute made the remainder of the match nervy, with the final whistle going at 2-1 to South Korea.

They now lead Group C with six points, while Uzbekistan moved up to second after defeating China 2-0. 

Islom Kobilov and Nurillo Tukhtasinov both got on the scoresheet.

In Group B, Syria overcame Japan in a dramatic 2-1 win at Thammasat Stadium in Rangsit.

Abd Al-Rahman Barakat successfully converted a penalty in the eighth minute, before Japan equalised through Yuki Soma in the 30th minute. 

Alaa Aldin Dali then put Syria 2-1 up in the dying minutes of the game to secure the victory for his team. 

Meanwhile, Saudi Arabia and Qatar played out a 0-0 draw. 

Group D is due to be in action tomorrow, with the United Arab Emirates taking on North Korea and Jordan meeting Vietnam.  

As Japan have already qualified for Tokyo 2020 as hosts, the remaining three semi-finalists will book their Olympic places should they reach the last four.

If not, the two finalists and the winner of the third-place playoff will advance.

The top two teams in each group will reach the quarter-finals, with the final scheduled for January 26 in Bangkok.