Rak-Sakyi is on loan at Charlton from Crystal Palace, but it has been suggested the Eagles could send him elsewhere this month and he has interest from other clubs, including Barnsley.
Charlton want to keep hold of the 20-year-old though and their chances of doing so have been boosted.
He completed the full 90 minutes at Fratton Park, scoring Charlton’s first goal in their 3-1 win, and the goal has boosted the Addicks’ chances of keeping him.
Rak-Sakyi has so far made 20 appearances in League One for Charlton this season.
Palace are likely to continue keeping an eye on Rak-Sakyi’s situation, with Charlton next in action at home against Lincoln City on Saturday.
The Addicks recently appointed Dean Holden as the new man in charge at the Valley.
The win at Portsmouth means Charlton now sit in 16th position in the League One standings and are ten points off the last playoff spot.
