Therefore, Berthelin will keep his place between the sticks for the trip to Anfield for the game to decide who plays Leeds United in round five.
Francis said: "I don't have any worries about Cedric. I had to throw him in against Leicester and he didn't let me down. He won't be fazed by this.
"We learnt about him when he was at Luton. They wanted to sign him but the finances wouldn't allow it and we jumped in to bring him to the club.
"He came on in the third round against Blackpool and he's done well in the league."