The former AFC Wimbledon striker has featured just nine times for the Tractor Boys following his free transfer move from Plough Lane in the summer.
Ipswich saw off competition from the likes of Bristol City, Luton, Sunderland and Pompey to land the 27-year-old, who ended last season with 22 goals in 52 games as the Wombles retained their League One status.
Yet he’s been unable to break his way into the side on a regular basis, starting just four of Ipswich’s 16 league games to date.
Cook admitted the form of 11-goal top-scorer Macauley Bonne was a key factor, along with the form of some of his other in-form forwards.
Speaking at a fans’ forum on Monday night, Cook said: ‘I apologised to Joe Pigott over the weekend for the lack of minutes that he’s had.
‘One of the things that as a staff we debate is that it’s very difficult to take Macauley Bonne off a pitch, it’s very difficult.
‘If you look even on Saturday, (Conor) Chaplin comes on, Sone Aluko comes on, who have scored goals, we’re always bringing goalscorers on in general.
‘I 100-per-cent agree with you, Joe Pigott should possibly have had more minutes, but if you look at Chaplin, who has gone in as a 10 and has got five quickly, (Bersant) Celina’s gone in as a 10 and has got goals quickly, Aluko’s gone in and got goals quickly.
‘There’s only Kyle Edwards now that we’re looking at and obviously working with Kyle on getting that assist and goal-rate up because the front four of the team has to score goals.
‘I agree 100 per cent with you, Joe Pigott especially should have had more minutes and hopefully he’s going to start on Tuesday night and hopefully we can see a little bit more of Joe.’
Along with Pigott, Pompey missed out on a move for Charlton forward Jayden Stockley in the summer.
However, manager Danny Cowley is determined to bring in a striker in January following John Marquis and George Hirst’s struggles in front of goal this term.