City are on the verge of going out of the Champions League, and whilst their Premier League title defence is on course - sat as they are just two points off top-spot - they have been far from convincing.
But Vieira - who himself tasted title glory during his playing days with Arsenal - admits it will always be tough defending their crown.
"Everywhere you go it is going to be difficult," City's football development executive told Sky Sports.
"We are not playing our best football, but we are at the top fighting with Man United and Chelsea and we are in a good position."
Vieira feels that City's ability to come from behind, which they are becoming increasingly adept at, is no shock given the strength of their strike-force.
"This is the strength of the club, the team and when you have the quality like we do up-front you can score at any point and it shows the character and that the team wants to be successful."
The French legend does not read too much into their continued Champions League struggle.
"So many teams want to win the Champions League but there can only be one winner. Champions League football is new for this club. We will see what will happen over the next few years."
Vieira added that he believes questions over Roberto Mancini's position as manager at Manchester City is an inevitable consequence of the club's success.
"That is a part of the game," said Vieira.
"People are like that and you people, journalists, try to find the little things that will sell more papers and will get more people listening to the news.
"But this is a part of our game and we accept it, no problem at all."
Mancini's future has been called into question, but again Vieira insists that long-term stability is important.
"I hope (he is here in five years) because I believe that stability will bring success to the football club, to any football club," he continued.
"When you look Man United is a perfect example to follow, so why not?
"I think Mancini, since he's been at this football club, his record has been fantastic.
"So credit to him - you're not winning the cup and winning the league as an average manager. You have to be good.
"He's a winner. He's working hard all week in training, trying to make the team focused and is really aware of the tactical aspect of awareness of the game.
"He is looking for the perfect game and he's really demanding. I think this is why he's so successful."