Jason Pearce and Chris Solly have been ruled out for three weeks through injury.
Pearce re-injured his knee in training during the week, while Solly has a calf problem.
Robinson said: “It’s three weeks for both of them, Pearce opened up his knee a little bit when he had a shot in training.
“Solls’ calf has been bad for a few weeks - he sort of tried to play through it. He couldn't make this game, we scanned it and he’ll be out for a few weeks.”
To add to their injury woes, Leon Best was forced off with a hamstring injury in the 1-1 draw against Blackpool today. It is likely to sideline him for the rest of the Christmas period.
However, Robinson confirmed three crocked players will return for the Southend clash on Boxing Day, but wouldn't reveal any names.
Charlton were without first-team regulars Solly, Pearce, Jake Forster-Caskey, Tariqe Fosu, Patrick Bauer, Ricky Holmes and Billy Clarke for the Blackpool game.
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