Mandaric, who gave caretaker boss Stuart Gray an extended period to prove his credentials before Christmas, also wants to concentrate on signing two players in time for the Yorkshire derby at Hillsborough.
"I'll talk to Stuart after the game at the weekend and we'll sort it out," Mandaric told the Sheffield Star.
"He has stabilised the team and the players are showing a lot of good signs. We cannot ignore that.
"We'll come to a final decision, but we want to concentrate on this important game against Leeds.
"Stuart is a good coach who is doing a good job. I'm very appreciative of that. He will stay one way or another.
"I cannot say now that he is going to stay as manager. I need to sit down with him and speak to him. It is a two-way thing."
Gray is expected to be handed the role after lifting Wednesday out of the relegation zone with three wins and two draws from seven league games since Dave Jones was sacked at the beginning of December.
Mandaric added that he hopes a replacement for central defender Roger Johnson, who has joined West Ham, and a new striker will be included in Gray's squad to face Leeds.