Pompey fans are to march through the city today before a friendly match with Bolton Wanderers.
Hundreds of fans are expected to turn out for the march as the club stares down the barrel of liquidation on August 10.
Fans will meet at 12.30pm in High Street, Old Portsmouth, where Pompey were founded in 1898 before meeting more supporters in Guildhall Walk an hour later.
It has been put together by lifelong Blues supporters Liam Bullard and Mike Probert, who want fans to show unity in the club's darkest hour.
They are hoping for similar scenes of SOS Pompey's march ahead of the FA Cup fixture with Sunderland in January 2010.
Thousands turned out for the walk to Fratton Park as the then Premier League club stared administration in the face.
Liam Bullard said: 'We have sat around as fans long enough.
We need to make a stand before we lose the club.
'We thought that rather than having a sit-in on the pitch - which costs the club money - a march would be the best option.
'We are hoping for a similar turn out to SOS Pompey's march against Sunderland in the FA Cup a couple of years ago.
'It's a case of giving the fans the voice that they should have.
'This could be the last throw of the dice if Trevor Birch is saying we have got a few days left. A lot of fans are divided, so we are trying to unite the fans as one.'
The march has been endorsed by supporters' campaign group SOS Pompey.
Its co-founder Bob Beech said it was a 'fantastic' opportunity for Pompey fans to join together and show their support.
He said: 'They have really pulled this together.
'Someone asked me the other day if the march is for or against anything. It doesn't need to be for or against anything.
'Fans moan and groan about what's going on but they need to have the chance to come out and show they care about the club. It's part of the "reclaim the club" mentality.