Norrington-Davies is currently on-loan with Stoke to the end of the season.
O'Neill says he is a defender who plays on the front foot.
“Rhys is a player who needs to play on the front foot," he said after the win against Wycombe Wanderers.
"He steps into the game and he's decisive.
“I think he's probably suffered a bit since he had the red card (against Huddersfield at the end of January). He's not played with that same real purpose or vigour that he did in the opening games here, when I thought he looked terrific.
“I thought in the second half we saw the player we brought into the club."