Celtic beat Union 2-0 in the first leg in Kinshasa last week and are in a very good position to advance to the next stage.
Phunya Sele Sele are yet to decide on the man to sit on the bench at Dr Molemela Stadium after John Maduka missed the trip to Congo last week.
According to CAF rules, coaches without a CAF A Licence are not allowed to sit on the bench in CAF tournaments and it is still not clear whether Maduka has the qualifications.
"John Maduka missed the game in Congo because we were playing against Leopards [before that]. We still have to decide who is going to sit on the bench tomorrow," Celtic CEO Khumbulani Konco tells snl24.com/kickoff when pressed on the issue.
Konco has, however, assured the club's fans that his team will field a strong starting line-up against the visitors from Congo.
"Unfortunately we don't have the luxury of having two teams. We will field the best team we have in the CAF game tomorrow," he adds.
Meanwhile, Neo Maema could miss the MTN8 final against Orlando Pirates in Durban next week and is set for a scan to determine the extent of a hand injury.