A shin problem in his left leg was assessed in the teenager’s second training session following his June 2021 arrival from Bromley.
Although now back in training, the left-back’s involvement is sporadic, still suffering from issues connected to the problem.
As a consequence, Vincent is booked in to see a specialist early this month.
And, at this stage, Cowley is unable to pinpoint just when the Fratton faithful will catch a first look of the promising talent.
Pompey’s head coach told The News: ‘Liam is okay. He has been able to train, but we have to cap what we’re able to do.
‘It’s a very gradual process when you have these stress fractures, particularly to weight-bearing bones, such as the tibia.
‘The shin bone is the major weight-bearing bone and the nature of these stress responses to bones can be very, very difficult to navigate through. It is proving to be very, very stubborn.
‘I know he’s getting really frustrated by that. Equally, we are frustrated by that because, in the training he’s done with us, he has shown what a talent he could be – but at the moment we are restricted because of the injury.
‘Liam is back with a specialist early this month, so it will be really interesting to get more guidance and more feedback and continue to try to help him through this period .
‘We have to remember that he’s a human being first and foremost and, while we are all frustrated, there will be nobody more frustrated than Liam.’
At the end of November, Vincent was surprisingly named as a substitute in successive League One games at Lincoln and Gillingham.
Yet he was unused – and then suffered another injury setback, putting him on the sidelines once more.
As of yet, he has still to make a Pompey appearance at any level.
Cowley added: ‘There’s a back-to-play protocol and this has been a very, very gradual one.
‘The bone has responded inconsistently on a day-to-day basis and it’s for us to keep trying to understand Liam and his body, understand where the injury is at, and to keep planning his training accordingly.
‘Liam is back with the specialist early this month and we’ll know more off the back of that.’
A message from the Editor, Mark Waldron
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