The enterprising duo will not be in action owing to their accumulated card offences.
Liadi was red-carded during Rangers’ matchday 5 tie away to Salitas in Ouagadougou after bagging two yellow cards in that feisty tie.
Okpako was also booked in the away tie against the Burkinabe team and that has made him ineligible for the game against the visiting Tunisian side.
Coach Gbenga Ogunbote’s tutored side are desperate for a win against CS Sfaxien even though they are aware that a good result in Enugu alone will not guarantee their passage into the quarter-final stage of the competition.
It will require a surprise away victory for Salitas at Etoile du Sahel for the Flying Antelopes to progress.
Going into the last set of group games, Sfaxien are at the summit in Group B with nine points from five matches and have qualified for the quarter-finals regardless of what happens in Enugu or elsewhere.
On their part, twice Caf Confederation Cup winners Etoile du Sahel have seven, while Nigeria’s representative has five and Salitas four from five matches apiece.