Celtic were confirmed as Maribor's opponents after an appeal from Legia Warsaw was dismissed by the Court of Arbitration for Sport.
Simundza had anticipated that outcome, sending assistant coach Sasa Gajser to scout Celtic during league wins over St Johnstone and Dundee United. The latter team were defeated 6-1 at Parkhead on Saturday and the Maribor manager intimated that he is wary of Celtic ahead of the first leg match in Slovenia tomorrow.
"I've spoken with Sasa who has watched Celtic closely for their past two games," said Simundza. "He's just confirmed what we already know: Celtic are a massive club with big traditions and are strong favourites against us. Sasa was very impressed when he watched them on Saturday. They were a constant danger going forward and were quick and strong.
"His job was to find a weakness in Celtic, but obviously we won't be revealing his answers to that question. But I would say that we are confident of finding that weakness [tomorrow]. Work starts now to find a way to beat this team."