Nicke Kabamba has joined Colchester United on loan.
The striker has moved to the League Two club until January in a bid for first-team experience.
On a busy transfer deadline day, Oliver Hawkins arrived Fratton Park to strengthen the forward options, while Michael Smith departed by mutual consent.
First-team chances remain restricted for Kabamba, however, so he has been allowed to link up with Colchester to continue his development.
In other deadline-day dealings, Stuart O'Keefe and Damien McCrory have joined the Blues, while it is hoped a deal can be finalised for Matty Kennedy.