And the promising winger remains locked in for a 2022-23 season return after rupturing cruciate ligaments in his left knee.
The former Manchester United and Birmingham winger suffered heartbreak just four days after signing a Pompey deal following a successful trial.
He sustained the season-ending injury in July, just seven minutes into a substitute appearance at Luton in a friendly.
Reid has now undergone surgery, with Pompey encouraged by the outcome.
However, due to the severity of the injury, Cowley is adamant there will be no return ahead of schedule for the highly-regarded 20-year-old.
Pompey’s head coach told The News: ‘Post-op, Jayden is all right. These are early days, but it has been clean and all is positive, so that’s good.
‘We need to support him now, there is a little bit of light at the end of his tunnel, which is good.
‘That time when you do the cruciate is horrible. You then have to wait to get the extension back into the knee before they can operate.
‘You then have to get a lot of work into it to bring the inflammation down to make the operation.
‘Jayden is now with us rehabbing, he has stayed down here and it’s going to be nine months.
‘You never come back before nine months with a cruciate. Well you can, but the risk of re-rupture is huge, so you shouldn’t.
‘You see some mad people do it. It’s not advisable.’
That would put Reid on target to return to action in the summer of 2022, potentially for the start of pre-season training, which is traditionally the end of June.
Cowley had high hopes for the winger, having impressed on trial following his summer release from Birimingham.
He first caught the eye of supporters as a second-half substitute for Ronan Curtis in July’s 5-2 friendly win at the Hawks.
Invited to remain for the subsequent week-long training camp at St George’s Park, Reid also featured off the bench against Burton and Bristol City.
Those encouraging displays earned him a one-year deal, with the club also possessing the option to extend it by a further 12 months.
That clause provides the former Manchester United youngster with crucial security considering the injury he would later suffer.
It means that despite being ruled out for a year, Pompey could stand by him and activate the additional 12 months to continue assessing his talents.
A message from the Editor, Mark Waldron
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