Naby Sarr missed Charlton’s win over Oldham after injuring his hamstring in the warm-up.
The Addicks defender has impressed since returning from a loan spell in France last summer.
He joins Jason Pearce, Chris Solly, Jake Forster-Caskey, Tariqe Fosu and Billy Clarke on the sidelines.
Robinson told News Shopper: “He [Sarr] had a fitness test today on his hamstring. It’s not massively bad - it’s only a grade one.
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“The pitches have been extremely flooded at Sparrows Lane and one or two players have picked up niggles.
“The amount of water that fell on Sunday night, it’s not as bad as it is in New York, but it’s been hard for the players.
“So I’m really pleased for them [with the Oldham win]. The desire was there. There was frustration because we were all so desperate for the win.
“I said to the players ‘when you get so much frustration it’s because you care so much’. It means so much to the fans. We’re one point off the play-offs - we’re in a great position.”
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