Captain Callum McGregor is in no doubt of Yang’s importance.
“He is a really important part of the team,” the captain told Sky Sports after the 2-1 win in Paisley. “He’s a big player to miss, but obviously we wish him the best.”
Yang’s stats are impressive. Two goals and an assist in seven games this season reflect his growing influence in games.
Last term, he scored 10 goals and provided three assists.
Width is a critical element to how Celtic are playing this season, and Yang would likely be the automatic choice on the left were it not for his international commitments.
South Korea will be up against Qatar and Saudi Arabia in Japan later this month.
Back in Scotland, Celtic travel to face St Johnstone in the Scottish Premiership before a trip to Rangers in the League Cup quarter-finals, a home Europa League game with Ferencvaros, then a home league Old Firm derby.