The Arsenal forward was expected to miss Denmark's opening 2-0 loss to the Netherlands and the 2-1 victory over Cameroon, a game in which he scored, but won his battle with a groin problem on both occasions.
Now, with just 90 minutes separating the Scandinavians from a place in the next round, Bendtner continues to struggle with the injury that has plagued him for almost the entire season.
Bendtner has already been singled out as the danger-man in Rustenburg for the Asians by its coach Takeshi Okada and Olsen said: "First of all we have to see if he can play and then we will decide.
"He has been doing quite all right. It's by necessity that every other day he does not participate in the practice.
"Every time he has played we wait to see the reaction from his injury. There's always a doubt when we have injuries like that, so we will have to wait and see."
Teammate Daniel Jensen, though, was ruled out by the Danish boss, while Simon Kjaer is suspended.
Olsen admitted he was "not nervous, but excited" ahead of the clash which his side must win to guarantee progress.
Both sides have lost to the Dutch so far but wins over Cameroon have put them on three points each, with a draw in the match at the Royal Bafokeng Stadium favouring the Asians and their slightly superior goal difference.