Milan 'disappointed' with some fans
Mandaric told BBC Sport: 'I was disappointed with some fans' attitude when Harry came back from Southampton.
'I appreciate it was an emotional time but I'm happy they're coming back round with the decision to bring him back.'
Redknapp was given a contract until the end of the season upon his return to Fratton Park from Southampton.
'If the worse should happen, we would want Harry to be the man to get us back into the Premiership.'
Milan did comment on the fact he needs Harry to focus.
'Harry understands that but he also knows that we want him to stay, so he can do his job with that knowledge.
'So there is no rush but at some time between now and the end of the season we will sit down and start to talk.'
Mandaric insisted: 'We are not thinking about relegation and we obviously think we can stay in this division.
'But if the worse should happen, we would want Harry to be the man to get us back into the Premiership.'
During Pompey's 3-1 win at Fulham on Saturday, supporters chanted Redknapp's name for the first time since he came back to the club.
Mandaric said: 'I think the vast majority of supporters were with my decision to bring Harry back, I think it was only a minority that were against it.
'But I'm happy that they have come around to my way of thinking.'
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