And they have warned other plans are also being drawn up to demonstrate their disapproval of the controversial competition.
The protest group have reformed to challenge the Football League’s decision to overhaul the former Johnstone’s Paint Trophy.
Pompey have been vocal critics of the introduction of Premier League under-23 sides, voting against a format subsequently brought in for a one-year trial.
They are backed by SOS Pompey, who on Monday night held a meeting at the Milton Arms.
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The group do not want the Blues to suffer financially through a boycott of scheduled home fixtures against Reading under-23s and Bristol Rovers.
However, spokesman Bob Beech believes a walk-out can be an effective protest.
He said: ‘At the meeting we discussed various ways of protesting, from boycotting to the Charlton method of throwing tennis balls on to the pitch.
‘We were the vanguard of making it a fan-owned club and are proud of that.
‘Yet we still have a duty of care to the club, especially when Pompey were one of the very few who stood up to be counted by voting against this.
‘Getting games abandoned would cause the club problems, so that was ruled out immediately.
‘Then we discussed the fact it is going to cost Pompey money to put these games on in a competition they don’t want to be in.
‘Clubs have to pay for stewarding, regardless of boycotts, so buying a ticket at least helps Pompey a little financially.
‘So we’re going to attend the game and the moment the referee blows the whistle to kick off, show our contempt for the competition and the Football League by getting up and leaving.
‘We have other things in mind which, for now, will remain under wraps.
‘A march on the Football League headquarters is very high on our agenda and we are still open to suggestions.’
SOS Pompey have already held discussions with Oxford United supporters also eager to protest.
And they are hoping fans across the country will unite.
Beech added: ‘The Reading game is the one we are targeting in particular.
‘They shouldn’t be in the competition. It is supposed to be a cup for minnows to see their club go to Wembley and win a trophy, that is the whole point.
‘We have contacted the Football Supporters’ Federation because we want to start getting fan groups together, united as one.’