South Africa had trailed 17-9 at halftime but hit back with two quick-fire tries to seal a hard-fought 29-25 win over Wales at the Millennium Stadium.
The victory maintained South Africa's 100 per cent record on their European Tour with games against Scotland and England to come.
"We have one focus and that is on Scotland," said de Villiers.
"That's very important for us. We have to carry on the momentum we have gained but make sure that we just focus on one game at a time.
"A lot of things can happen in a week so we will just play that game and then we will start speaking about the final game after that.
"The World Cup is 10 months away. They could fire me, we could have injuries or lose form. There are a lot of things that could happen. We take it one game at a time. The confidence levels are improving for us.
"The players showed what the jersey means to the team. We put in some real big hits at the end against Wales.
"At halftime I told the players they had let themselves down. But they could make it happen for themselves, I said to go back out and play. Make it happen.
"I'm a very positive person but I knew Wales could come back. We have the experience of that in the Tri Nations where we lost a game in the 80th minute to a penalty.
"But the players showed a lot of character. Our organisation was good and we made four offensive tackles which kept us in the game."