But he is adamant Pompey’s new owners have prioritised the transformation of Pompey’s infrastructure.
Tornante last week completed the anticipated £5.67m takeover of the Blues, with Michael Eisner installed as chairman.
Chief executive Catlin has also agreed to remain under the regime, signing a long-term contract and handed a place on the six-man board.
The future of Fratton Park continues to be a burning issue, particularly with an estimated £5m worth of improvements required to maintain its well-being.
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Eisner has reiterated his desire for the club to stay at their 119-year home and before last weekend’s visit of Rochdale led a delegation around the ground assessing what requires attention.
Change is clearly on the agenda away from the pitch.
Yet Catlin has called for supporters to be patient as Eisner draws up his Pompey blueprint.
He said: ‘Tornante’s absolute priority is Fratton Park, infrastructure and match-day experience.
‘That is not something you can just suddenly change overnight, it is going to be a long process.
‘There will be a lot of investigation, there will be a lot of due diligence – a lot of it has already been undertaken – but they will put fan experience at the forefront of everything they do.
‘They have never once said it will be a quick fix – and I have never once said it will be a quick fix. The reason for that is because there is no quick fix.
‘They have bought into a club which has prided itself on sustainable growth and that is exactly the same path they are now going to follow.
‘That was made clear during the build up to the vote, the fans knew what they were voting for – and they will get it.
‘These are extremely exciting times for Portsmouth Football Club, myself and the staff.
‘Having spent time with Michael and his group, we are excited about the future and what it holds for everyone associated with the club.
‘But this has to be tempered with expectation and the fact that to get it right there are no quick fixes.’
The Eisner family have now returned to America – amid promises to come back to Fratton Park when schedules allow.
In the meantime, it’s business as usual for Catlin and finance director Tony Brown in what is now their fifth season with Pompey.
During that period the Blues have become debt-free and self-sufficient – a status the club’s chief executive is eager to retain.
Catlin added: ‘We are going to continue on the same route of sustainable growth. Pompey will be strong and everything we do will be carried out in the correct manner.
‘One of the biggest concerns of fans at all football clubs is the owner and the decisions they make.
‘At Pompey we now have an owner I believe will not only continue the work of the previous four years, but enable us to build sustainably on strong foundations which have already been laid.’