South Korea head coach Shin Tae-Yong has put a question mark over the availability of Swansea City midfielder Ki Sung-Yueng for his nation's crunch World Cup qualifying match against Iran on Aug. 31.
The Koreans need to pick up a win against the Iranians, who have already qualified for Russia 2018. That would get their campaign back on track following a loss against Qatar in early June that put the country's hopes of qualifying for a ninth straight World Cup in jeopardy.
Ki underwent knee surgery during the Premier League close season while Son Heung-min has recovered from breaking his arm during the defeat in Doha.