Ryan Bird has left Pompey by mutual consent in an attempt to secure regular football.
The 26-year-old was contracted to the Blues until the end of the season.
Yet with Bird eager for first-team opportunities elsewhere, that deal has now been ripped up.
The former Burnham player made 25 appearances and scored three goals following his Fratton Park arrival in the summer of 2013.
But he has fallen out of favour at Pompey of late, failing to make Andy Awford’s last four matchday squads.