Disappointingly, a back injury has ended the January recruit’s campaign prematurely, ruling him out of the final seven matches of 2021-22.
Even before then he had slipped out of the left-back reckoning, with Connor Ogilvie instead preferred.
Still, he has been restricted to nine outings since a £200,000 switch from Sunderland.
And Cowley anticipates the 23-year-old will be injury-free and back challenging for a spot in the build-up to next term.
Pompey’s head coach told The News: ‘Denver had a little prolapsed disc in his back, which sounds a lot worse than it is.
‘It’s just a minor bit of swelling, but there’s some nerve irritation, so we have settled it down with an epidural.
‘He’ll be back for pre-season. He would have been back within a couple of weeks, but obviously the season ends after Saturday.
‘I’m looking forward to seeing him back, we know he’s a young player with lots of growth, unbelievable athleticism, speed and pace.
‘We think he can really add to the group.’
Following his arrival, Hume was handed a debut in January’s 2-1 defeat to Charlton.
He subsequently started six of the next seven matches, catching the eye at times with his attacking runs and willingness to test a full-back.
However, last month he developed back issues which initially forced him onto the bench as a non-playing substitute, before dropping out of the squad entirely.
In addition to Hume there is Ogilvie, who finished third in The News/Sports Mail’s Player of the Season after a superb opening campaign at Fratton Park.
The former Gillingham man has also spent long spells at centre-half, although in recent weeks has operated at left-back in a conventional back four.
Completing the options is Liam Vincent, who has endured an injury-wrecked campaign, yet returned to action in February.
He has turned out four times for the Academy in order to build up match fitness, while has been an unused substitute for the first-team on six occasions since his comeback.
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