The 2-0 win at The Valley was the first time the Reds had not conceded a goal in 13 matches since drawing 0-0 at Brighton on December 15.
"It was a very important clean sheet," said Davies, who has won seven points from three games since returning for a second spell in charge at the City Ground.
"We asked (the players) for it before the game. We probably deserved it in our last two matches, but a little bit of slackness in our play cost us dearly.
"But I am pleased for the back five because we have worked hard this week on certain aspects of our game. It will give them a bit of confidence.
"Karl (Darlow) is a young player and we know what he needs. But you can talk about him, the back four, the front two - it was a great team effort and a great team performance from back to front."