The 20-year-old has been with the Blues first-team set-up at their Roko training base as he looks for a new club.
Danny Cowley confirmed the midfielder has been present for a section of pre-season and sung the praises of the Londoner’s potential.
De Havilland progressed through the youth ranks at Craven Cottage after joining the club from Reading as a child.
He failed to make a significant impact at first-team level, however, with his only appearances being three EFL Trophy outings last term.
That led to a departure in June, as one of nine players told they were not being handed a new deal.
Now Danny Cowley is running the rule over De Havilland - and there is a lot he likes about his game.
He said: ‘Ryan De Havilland is here.
‘Ryan has been here for a lot of pre-season.
‘He’s a great kid, very technical and a really good footballer.
‘He’s a lovely footballer and he makes training better every day.
‘He’s between clubs, so he’s helping us and we’re helping him. It works for us both.’
As an out-of-contract player there would be nothing to stop Cowley offering De Havilland a deal if he was keen.
The Pompey boss has spoken of his desire to have a group of promising young players on the fringes of his first team.
Jayden Reid and Liam Vincent both fall into that category, although both are currently injured.
Cowley confirmed talks are ongoing over a deal for Jay Mingi, despite his threat of legal action against the club.
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