Premier League - Fergie in new Vieira warning
City's football development executive Vieira claimed that Roberto Mancini's side deserve to pip United to the crown this season because they were the most attractive team to watch.
But Ferguson said: "They were playing great football in the first half of the season. Everyone recognised that and we felt the brunt of it too when they beat us 6-1 here. But a season lasts for a bit longer than three months."
Vieira's comments were made in a longer interview with the BBC which the Frenchman later claimed had been misrepresented.
Vieira was quoted as claiming United receive favourable treatment from referees at Old Trafford, but City then banned BBC reporter Dan Roan from the club's facilities as they claimed the quotes were taken out of context - purporting to be a reaction to Fulham's failure to win a penalty at Old Trafford on Monday night when Vieira had made it clear he did not see the game.
Ferguson has been left perplexed by Vieira's latest outbursts, coming just a week after his jibe that "desperation" was behind Paul Scholes' retirement U-turn. That triggered a blistering response from the United manager, and an accompanying warning that he had "plenty of ammunition" if City wanted to engage in mind games.
Although he ended his career with the Blues, it is Arsenal with whom Vieira is most synonymous, and in particular his midfield duels with Roy Keane - battles Ferguson seems willing to restart.
"We can bring Keane back if he wants and make it interesting," said Ferguson.
"Apparently he's retracted [the comments] a bit but it's interesting. The thing is, from the referee's position, I can see why he didn't give a penalty when Danny Murphy was brought down.
"The ball moved to the angle as Michael Carrick challenged him and from that position, it wasn't clear. It was a good claim but you could go through millions of things like that. Every club gets breaks here and there, you get good ones and bad ones. It evens itself out over the season, that will never change."