"They [Portsmouth] are on a good run of form, they've hardly been beaten at home," said Duncan Ferguson.
"They're a good team, they'll be favourites for the game, their striker, Colby Bishop, is scoring a lot of goals.
"We're up against it, but we've got a bit of confidence behind us, so let's get in there and have a go."
"Prior to the win against Sheffield Wednesday, they [Forest Green] had a bad run of results but they'd been unlucky in a couple of games," said Pompey boss John Mousinho.
"We watched them at Accrington and they were by far the better side before they had a man sent off. They're a good side but they've just been a bit unlucky.
"Watching them on Sunday, you wouldn't think they're a side who are cut adrift at the bottom of the league. They had confidence, they were well-organised and they were really good value for the win."
Corey O'Keeffe will serve the second game of his two-match-ban, while Olly Casey is available for selection once again after serving the final game of his three match ban.
Ben Stevenson and Charlie McCann remain sidelined, as do trio Tyler Onyango, Jahmari Clarke and Baily Cargill. Dylan McGeouch (calf) is a doubt.
Tickets for this fixture are no longer available.
There will be NO tickets available for purchase at Fratton Park on the day of the game.
Referee - Paul Howard
Linesman - Marc Wilson and Jonathon Bickerdike
Fourth Official - Scott Williams
Full commentary of Saturday’s match will be available via our online streaming service and on BBC Radio Gloucestershire on 1413AM.
Stay up to date on Twitter by following @FGRFC_Official, which will have all of the team news before kick-off and updates throughout the game.
There'll also be key updates and team news on Facebook and Instagram.