And there are a number of highly experienced forwards who could fit the bill and fire the Blues up the League One table.
On the other hand, the club may also look to the loan market once again if they decide to free up one of their, already filled, spots.
Click through the list to see who is a viable striking option for Pompey in January.
1. Free agents
There are a number of highly experienced free agents that the Blues could sign on short-term deals in January. Picture: Joe Pepler Photo: Joe Pepler
2. Oumar Niasse (Former club: Huddersfield Town)
The former Everton striker may have a lot to prove after an underwhelming spell at Danny Cowley's former club Huddersfield. where he failed to make an appearance. (Photo by Catherine Ivill/Getty Images) Photo: Catherine Ivill
3. David Nugent (Former club: Tranmere)
The former Blues striker has entered the latter stages of his career following his release from Preston via a loan spell at Tranmere - but could be useful in a deal until the end of the season. Nugent scored twice in 18 League Two appearances for the Super White Army last term. (Photo by Lewis Storey/Getty Images) Photo: Lewis Storey
4. Hal Robson-Kanu (Former club: West Brom)
The Wales international has been without a club since his release from West Brom last term. However, at 32, Robson-Kanu could still have lots to give due to his experience and ability which could make him a prized asset in League One. (Photo by Clive Rose/Getty Images) Photo: Clive Rose