Mark Catlin has blasted the ‘catastrophic’ changes championed by football chiefs.
And The News understands the Whole Game Solution could cost Pompey between £600,000-800,000 every season in lost revenue.
The outcome for us would be catastrophic, running into many hundreds of thousands of pounds lost through the reduction of four home fixturesMark Catlin
Ahead of a June 2017 vote, the Football League are in the process of consulting its 72 member clubs on the Football Association blueprint.
The controversial proposals involve the implementation of a winter break, two FA Cup rounds taking place in midweek and the creation of five divisions, each consisting of 20 clubs.
Effectively, those sides outside the Premier League will stage four fewer home league fixtures every season.
The Blues currently average 16,628 from their three Fratton Park fixtures this season – in addition to healthy match-day receipts from food and corporate clients.
Furthermore, the reduction of the Championship from 24 teams to 20 would severely diminish the chances of those with promotion aspirations reaching it.
And the Pompey chief executive is adamant the Whole Game Solution will not receive the club’s backing.
Catlin said: ‘These proposals will impact on different clubs outside the Premier League in different ways.
‘As a fan-owned club, we don’t rely on external investment. We rely heavily on gate receipts as a percentage of total income to fund the club. They account for a huge part of the club’s overall turnover.
‘The outcome for us would be catastrophic, running into many hundreds of thousands of pounds lost through the reduction of four home fixtures.
‘It’s not just the pay-on-the-day custom we wouldn’t receive, you would naturally also have to reduce the price of season tickets as there would be four games fewer.
‘Corporate hospitality, kiosks, all match-day income is key to a club like Portsmouth, which is trying to be run in a sustainable way. With the greatest of respect, there are plenty of other clubs not so reliant on gate receipts.
‘Their proportion of income comes via either central distribution and solidarity payments from the EFL or huge external investor income.
‘We are being told self-sufficiency is the right way to run a football club – this is our model and we agree. Yet we are going to be one of those most affected by the proposed changes.
‘As for a 20-club Championship, what you are doing is beginning to make it elitist. You are taking away the aspiration of clubs to climb the league ladders.
‘Burton, Rotherham and Barnsley, as examples, have done absolutely amazing jobs in getting to the Championship.
‘But by reducing the league to just 20 clubs eventually you are going to prevent clubs like that being able to arrive there.
‘It will just become a league containing clubs with billionaire owners and those in receipt of Premier League parachute payments.
‘The reduction of league sizes is the big one for us, it really is. Winter breaks and all the rest we worry about, but they are not life threatening to the business.
‘For a club like Portsmouth trying to do things the right way, these changes will potentially kill our aspirations moving forward.’