Loan duo Mahlon Romeo and Hayden Carter emerged as Danny Cowley’s favoured figures for the position during the 2021-22 season, but have already returned to their parent clubs.
Meanwhile, the former Sheffield United man’s own Fratton Park future has been thrown into doubt, after reports emerged that he was being monitored by a trio of League Two clubs.
So who could the Blues turn their attention to in order to fill the void?
We’ve scoured the Championship for players who struggled for game time in the position this season, and identified the Premier League youngsters who could be looking for a new home over the summer.
Here’s who we found.
![Age: 20
2021-22 Championship appearances: 4
Picture: Catherine Ivill/Getty Images](https://www.portsmouth.co.uk/webimg/b25lY21zOjMyODA5NTY4LWQ4OWUtNGUxZi1hZWI0LWM4MDU1OGVlZTZjODoxMmVhZDQ5ZC02MTc4LTRmMGUtODlkNC04ZTEyZjdmY2MxNzY=.jpg?crop=3:2&width=640)
1. Tyrell Ashcroft - Reading
Age: 20 2021-22 Championship appearances: 4 Picture: Catherine Ivill/Getty Images Photo: Catherine Ivill
![Age: 27
2021-22 Championship appearances: 5
Picture: Michael Regan/Getty Images](https://www.portsmouth.co.uk/webimg/b25lY21zOjc4ZDc3MTJjLWRhZTItNDdmOC1iNTJkLTE1MmNiZjdjYzYzYTozN2M2NmVmNC1mYzFjLTQzNzUtYTAzYS05OTEyNGE2ZDA1ZjY=.jpg?crop=3:2&width=640)
2. Richie Laryea - Nottingham Forest
Age: 27 2021-22 Championship appearances: 5 Picture: Michael Regan/Getty Images Photo: Michael Regan
![Age: 24
2021-22 Championship appearances: 6
Picture: Jacques Feeney/Getty Images](https://www.portsmouth.co.uk/webimg/b25lY21zOmNkMTIzODk0LWNhMzgtNGZhMy04ZTIyLWE5NmMwODZiZGQ4OTo2ZmQxODgyMy1mOWVlLTQyMjAtODFhYS1lYzkzNDRhM2JjODY=.jpg?crop=3:2&width=640)
3. Josh Emmanuel - Hull City
Age: 24 2021-22 Championship appearances: 6 Picture: Jacques Feeney/Getty Images Photo: Jacques Feeney
![Age: 23
2021-22 Championship appearances: 12
Picture: Jacques Feeney/Getty Images)](https://www.portsmouth.co.uk/webimg/b25lY21zOjU4ZWVhM2I2LTljMzAtNDc4MC1iZDRiLTc5ZWE0N2RmNGYwNjo0OGYzMzMzOC1mNWNkLTQ2OWItODdiOS0zODM2ZDI3MjE5YmU=.jpg?crop=3:2&width=640)
4. Toby Sibbick - Barnsley
Age: 23 2021-22 Championship appearances: 12 Picture: Jacques Feeney/Getty Images) Photo: Jacques Feeney