De Bruyne was outstanding for victory at Wolves in City's first game of the season.
Guardiola remarked: "Since we came back from the international break, I have felt his eagerness to contribute to every training, and right now he is an important player for us - he will always be.
"In the situation we are in now, he is really important to us. His penalty kick (against Wolves) was strong and he played really well as did the whole team.
"He likes to play football, he does not feel the pressure and he likes to compete at a high level."