The 26-year-old is yet to feature for his country at the competition due to a hamstring problem, and he remains a major doubt for his side's third match in Group H.
South Korea need to overcome Portugal to stand any chance of making it through to the knockout round of the competition, but there is not expected to be a change of formation for this match.
Head coach Paulo Bento will again be looking to his captain Son Heung-min to provide inspiration on Friday, with the 30-year-old set to win his 107th cap.
Cho Gue-sung scored twice in the 3-2 loss to Ghana last time out, and he should again lead the line, with Kwon Chang-hoon featuring off the left.
Hwang In-beom should retain his position in the middle of midfield, while Jung Woo-young is also expected to feature in the starting XI for South Korea in this contest.
There are also not expected to be any changes at the back, with Napoli's Kim Min-jae, who has recently been linked with Manchester United, set to feature in the middle of the defence.
South Korea possible starting lineup: Seung-gyu; Moon-hwan, Min-jae, Young-gwon, Jin-su; Woo-young, In-beom; Chang-hoon, Woo-yeong, Heung-min; Gue-sung
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