In addition, last month saw the defender make his debut for Tanzania, accruing two caps during the international break.
Following the frustrations of a disastrous spell at Bromley in the first half of the season, Monga is thriving away from Fratton Park.
But Cowley wants to see the Somers Town youngster in action during pre-season before deciding whether he requires another loan destination to aid his development.
Pompey’s head coach told The News: ‘It’s great that Haji has been able to have a run of games, I anticipate 20 senior matches by the end of the season.
‘We’ll then put him into a position where he can really attack pre-season – and we’ll see what happens.
‘Progress doesn't always happen in a straight line, sometimes they have this experience where they go out on loan, play a run of games, and it almost gives them a snowball effect when they progress rapidly.
‘All the pieces of jigsaw fall into place, it’s experience, their decision-making improves, all of a sudden they get confident and that’s the springboard.
‘As soon as they start to believe in themselves, then the progress goes up.
‘You always be open minded, never put a ceiling on their development. That’s why I would never say Haji will definitely go out on loan next year - he might come back and it’s that springboard.
‘With young players, we want them to play. As soon as we don’t think they are going to play regularly for us, my tendency is always to try to create a loan for them.’
Mnoga has appeared 15 times for Pompey, two of which arrived in the Papa John’s Trophy this season.
It’s a first-team association which began with his debut in October 2018 at Crawley, while aged 16 years, five months and 24 days.
Cowley added: ‘Haji still has a lot to learn tactically and technically.
‘He has some fantastic physical attributes, such as athleticism, pace, power and strength, but he’s got to put it all together.
‘I see him as right of the back three at the moment, but that’s not a position. He has to be able to play right-back or right centre-half in a back four.’
A message from the Editor, Mark Waldron
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