The former Tottenham Hotspur and Queens Park Rangers manager emerged as a surprise candidate for the role at the Slovenian league leaders last week having worked with Mandaric before when the pair were at Portsmouth.
However, Mandaric has admitted that bringing the experienced boss in would be too much of a risk for his side, hinting that he will look to appoint a manager who already knows Slovenian football.
"We cannot afford the slightest error because there is too much at stake," Mandaric told the club's official website.
"We need someone for whom the Slovenian football environment is not foreign. It would therefore be pointless at this stage to engage experts from Western Europe.
"I know that it has recently been written and spoken about the arrival of my good friend and former colleague at Portsmouth, Harry Redknapp. I can assure you that (it will not be him) because we cannot afford too many risks."
Ljubljana have been without a head coach since Marijan Pusnik left the club last month, while Redknapp has now been out of football for a year have stepped down as QPR boss in January 2015.