Conor Chaplin had been earmarked to make way for Michael Smith at Luton before the issuing of his ban.
The teenager collected a fifth yellow card of the season during Saturday’s 1-1 draw at Cheltenham.
During his one-match absence, Paul Cook has confirmed Smith will be charged with leading the Blues’ line at Kenilworth Road tomorrow night (7.45pm).
Pompey’s boss insists the summer recruit had been informed before the Cheltenham fixture that he would subsequently be starting against Nathan Jones’ side.
Cook had pencilled Chaplin in for a substitute role following nine successive league starts.
That option was removed, though, after the Worthing youngster’s second-half booking for dissent on Saturday.
But the Blues manager is adamant the time was right for Chaplin to be handed a breather.
He said: ‘Believe it or not, Michael was starting against Luton before Saturday.
‘He is ready to play – and I think our fans will say Conor needs a rest following the amount of matches he has played on the spin.
‘That is the good thing about the squad, I have great faith in all the players.
‘People think you are a reactive manager, but I’m not. Michael knew before Cheltenham he would be playing against Luton.
‘Had Conor got a hat-trick on Saturday it would have been difficult to leave him out, but I would have.
‘Conor has played enough games quickly, but would have been a great sub to bring on at Luton for the last 20 minutes, so that was the plan.
‘Conor is part of what we do, they all are. It’s important we push this promotion bid and every player has a part to play and must be ready to play.’
Chaplin’s run of League Two starts began in September for the visit of Barnet.
He netted in that 5-1 victory and has remained there ever since, taking his season’s goal tally to five.
However, the striker has also collected four yellow cards in his past five league appearances to earn a suspension.
While he was harshly booked at Plymouth for diving, others have been for not retreating his distance and dissent.
Cook added: ‘You live with bookings when the player has not retreated, that is something we are trying to be more professional with – but not the dissent.
‘The dissent is a little bit of frustration and Conor can’t be getting booked for dissent.’