A number of fans have shown their displeasure at Brown's arrival with many of them walking out of a meeting with the board at Dens Park over the weekend.
Dundee remain 15 points adrift at the base of the SPL table and speaking after Sunday's 5-0 defeat by Celtic, the club's assistant manager said: "I don't know about John's credentials, all I know is that he will give it 100 per cent.
"And he will do everything to try to get the club moving forward and I'm quite sure he will because that is what we have to do now.
"We have big games coming up and the supporters need to get behind the team and the manager.
"It has been very difficult for everybody, the staff and the players but they have to get on with it.
"It is not John's fault, I have got to emphasise that, it is not his fault."