The Addicks come into the game off the back of a 1-0 away win at MK Dons on Tuesday. Liam Millar scored the winner in the 18th minute of the game for Lee Bowyer's side. Charlton have not recorded a home win since 12th December but a win on Saturday would see them overtake Portsmouth and stay in the play-off places.
They have won their last three away games in the league, keeping a clean sheet in all of them so Portsmouth will be confident that they can leave London with all three points on Saturday.
Akin Famewo, Marcus Maddison and Ryan Inniss are all doubtful for the home side because of injury. Jason Pearce and Jonny Williams were not involved midweek but could return to the starting lineup this weekend.
Portsmouth centre-back Jack Whatmough is suspended after receiving his marching orders against Lincoln midweek for a bad tackle.
Amos; Gunter, Oshilaja, Pearce, Purrington; Shinnie, Forster-Caskey, Pratley, Millar; Stockley, Washington.
MacGillivray; Johnson, Nicholassen, Raggett, Brown; Williams, Cannon, Harness, Naylor, Jacobs; Marquis.
Ones to watch
The 26-year-old central midfielder has crucial in the heart of Charlton's team this season with his brilliant mix of attacking and defensive qualities. Forster-Caskey is a danger from long range and free kicks yet is also very accomplished at tackling and intercepting. With two goals and one assist in the past five games, he is in red-hot form at the minute and could cause Portsmouth some problems on Saturday.
The Portsmouth centre-back has been rock solid in defence this season and could play a huge part in nulling the Charlton attack this weekend. Raggett has won four man of the match awards this season and has also used his aerial prowess to score twice.
Charlton have beaten Portsmouth in their last four meetings in League One, with the most recent being their 2-0 win at Fratton Park back on 31st October thanks to goals from Jonny Williams and Chuks Aneke.
How to watch
Kick-off is at 15:00 BST on Saturday 30th January and the match is available to watch on both club's iFollow streaming service for a fee of £10.