Vieira feels City's success this term fully vindicates the Italian, who he has backed to introduce a more expansive style of play in future amid continued criticism of a cautious approach.
Vieira told The Times: "I don't know what they asked from him upstairs, but we have the Champions League, an FA Cup final and clear improvement.
"I don't think the manager's future can even be an issue. All we can ask is to improve year on year and we are one step higher.
"You can see that. The results are proof."
"Be patient. Build like a house, they say. The foundations, the defence, the organisation. Then you can add more.
"There are young players and they need to grow together. We have changed so many players and you need time to build trust and understanding."