Deal maker Keith Harris says if Manchester United fans want the Glazer family to sell the club they must boycott season tickets and merchandise.
Harris is the man behind a proposed £1billion buy-out of Manchester United.
"'Turning up to games 10 minutes late and things like that just doesn't do the job," Harris told the Daily Mail.
"The green and gold protest is fabulous, a symbolic and significant message to the owners. It is like the white handkerchiefs in Spain. But that won't force the Glazers to sell to us.
"However, if enough people - and I am talking about thousands - stop turning up to matches and do not renew their tickets, then that does it. The supporters have to hurt the Glazers in their pockets.
"They have to be prepared to take the pain of not watching their club in order to achieve a long-term gain. Supporters have to be galvanised to say, 'We will not come. We will not buy programmes and merchandise'.
"It's a big ask, it's a risk, but that is what must happen. The Glazers are thick-skinned and seem impervious to protest. They will not be impervious to enormous drops in their revenue.
'I would not talk about this if I didn't have full confidence in our ability to raise the money to do this. I never talk publicly unless I have confidence. Getting the money together is the easy bit.
"But we can't make an offer until the Glazers are placed in a position where they are forced to consider it."