Son has only recently undergone surgery after fracturing his eye socket against Marseille in the Champions League for Tottenham Hotspur at the start of the month, and playing any part in this World Cup represents a huge risk.
Both Son and his compatriots will believe it is a risk worth taking though, as Korea are a completely different team with and without him, as he is their only top-class player and the main goal and creative threat.
Their other attacking options do not offer much encouragement given their recent form, including Son's fellow Premier League forward Hwang Hee-chan, who has yet to score for lowly Wolverhampton Wanderers this season.
Hwang Ui-jo enjoyed two productive seasons at Bordeaux, but since arriving at Olympiacos he has struggled for game time, although he is still expected to start as the central striker.
Bento will be under pressure to start attacking midfielder Lee Kang-in, as the Real Mallorca man is one of the few players in the side who can provide a creative spark in their midfield.
The manager has come under fire for his passive playing style which lacks pace and does not create many chances, and with five goal contributions in La Liga this season, Lee would be unfortunate to miss out.
Napoli's Kim Min-jae will be the lynchpin at the centre of the Korean defence, and could be one of five Kims playing across the back four and in goal.
With Son doubtful, there will be increased pressure on the defence to keep the goals out given the reduced goal threat in attack if Son is not fully fit, and the Napoli defender has proved what a colossus he is in Serie A this season.
South Korea possible starting lineup:
Kim Seung-gyu, Kim Moon-hwan, Kim Young-gwon, Kim Min-jae, Kim Jin-su; Jung Woo-Young, Hwang In-beom, Lee Jae-sung; Hwang Hee-chan, Son Heung-min, Hwang Ui-jo