Charlton are in talks with their former defender Jonathan Fortune over a move back to The Valley.
Fortune, 30, has been training with the Addicks since the summer and is a free agent after leaving Sheffield United at the end of last season.
"We're working on that one and there is a possibility he could re-sign," said assistant manager Tim Breacker.
"Centre-half is a position we need to cover. He was at the club when it was in a higher division and he played in the Championship last season, so maybe his sights were to try to get back there by using us to get fit.
"We were quite happy for him to do that, but now we're looking at him and thinking it would be good if we could get him in."
The Addicks remain on the trail of Dagenham striker Paul Benson, and Breacker added: "We've made enquiries about him, as we have with other players. I can't really say much more, but he's a player we like and, if possible, we'd like to bring him in."