Davis has until 6pm Thursday to appeal the charge.
Neil Warnock is not happy.
"The referee told us after the game that he saw it and thought it was inconclusive so I don't know what has changed his mind," he told the South London Press.
"There are just no comparisons between some of the challenges I've seen that haven't been punished. That's Claude done for the season now."
Roger Johnson, who spent two days in hospital missing the home game with Burnley on Monday, said
"It's clear for everyone to see what went on and it's clear in my eyes. I'm disappointed with the player.
"I wanted to stay on," he admitted. "But the physio saw me spitting blood, so it took the decision out of my hands. I wanted to play against Burnley, but I suppose it was sensible not to."
Johnson hopes to be back to face Preston on Saturday.