The former Pompey winger – who is currently out following an operation on his ACL – uploaded a one-minute, 20-second video onto social media of himself doing a series of drills at the Blues’ Roko training base.
The clip shows him testing his left knee in the gym and out on the grass as his ex-Blues team-mates train on an adjacent pitch.
The Republic of Ireland international also wrote on X, formerly Twitter: ‘Near the 7th month maker (sic) never felt so good looking forward to the next couple months #RC’.
The post on Monday followed calls from sections of the PO4 faithful for the winger to be handed a new Fratton Park contract.
Despite remaining at Pompey for the purpose of his rehabilitation, Curtis is no longer a club employee, having turned down heavily reduced terms upon the expiry of his previous Fratton Park contract in June.
Some fans believe he warrants an improved offer, though, especially as summer signing Anthony Scully looks set to sit out the rest of 2023 with a knee problem.
Curtis remains ahead of schedule as he recovers from the ACL injury he sustained in the 3-1 win against Bolton back in February.
A December comeback was initially pencilled in. And while there will be a need to remain cautious, there will be a hope that an earlier return date can be set.
Pompey head coach John Mousinho told The News earlier this month that there was still a chance Curtis could revive his Blues career.
He said: ‘We’re certainly not ruling that out (Curtis having a Pompey future).
‘The club and Ronan were apart on where they see it, but my take was it would be nice to have Ronan for another year to see if he could come back.
‘We obviously couldn’t work that out, but my opinion on that hasn’t changed.
‘If you can Ronan Curtis back fit and firing then he is a real asset.’
Curtis has been linked with the likes of Blackburn, Derby, Bristol City, Cardiff and Hibs in the past.
The Irishman is the Blues’ highest scorer of the 21st century following 57 goals in 226 appearances.