Paul Cook has acknowledged the benefits provided by the implementation of a 3-5-2 formation.
Yet he is adamant the option will continue to serve specifically as a Pompey Plan B.
There can be the belief a change in formation leads to a better result, but Saturday we had one of those team performances where everybody did their jobPaul Cook
The Blues tonight host Morecambe (7.45pm), seeking to build on the impressive weekend triumph at Carlisle.
That crucial victory was achieved following a 72nd-minute tactical change, with the match goalless.
Cook opted to switch from his favoured 4-2-3-1 system to one with a back three, which included substitute Jack Whatmough.
He also paired Conor Chaplin and Eoin Doyle in a two-pronged attack.
The final 3-0 scoreline strengthened Pompey’s hand considerably in the hunt for automatic promotion.
But the Blues boss will not ditch his preferred formation for the 3-5-2 during tonight’s visit of the Shrimps.
He said: ‘The reason we have gone 3-5-2 in two of the last three games is to combat what the opposition were doing.
‘Blackpool were throwing more men forward, putting more balls into the box, like Plymouth did at Fratton Park last year when we dropped a 1-0 lead to lose 2-1.
‘On Saturday, Carlisle brought on Jabo Ibehre up front to partner Jamie Proctor to play with a little bit less flair.
‘We feel we have the ability to counteract what everyone does and, amid that, when we get to the latter stages of games we are fit.
‘There can be the belief a change in formation leads to a better result, but Saturday we had one of those team performances where everybody did their job.
‘Like any club, when we get it right, it’s good. When we don’t get it right, it’s a work in progress.
‘I don’t see the need to start lining up with a 3-5-2. If you look at our two substitutions against Barnet, we are now very comfortable with the fact we can change it during the game and also at half-time.
‘Repetition among the lads is good and the lads believe in what you do. Our lads are comfortable with what we do.
‘I prefer to let supporters debate it – and I prefer to keep doing my job to the best of my ability.’
Pompey have collected 10 points and three clean sheets from their past four matches to crank up the momentum.
Following successive away fixtures, it’s back to Fratton Park.
And Cook’s tried-and-trusted system will remain in place.
He added: ‘For people who think 3-5-2 is attacking, you want to have a look at Chelsea.
‘How many attackers do you think they have? Do you think Kante, Matic, three centre-halves and a goalie is an attacking formation?
‘It’s about making use of the personnel you have, that’s the reality of every formation.
‘Leam Richardson enjoys that (3-5-2) formation a bit more than I do, but that is football, it’s debates.’