Keane believes the only team that can realistically threaten more Old Trafford domination is their bitter local rivals - big-spending Manchester City.
Keane told The Sun: "Even Sir Alex Ferguson said the other day the league's getting tougher. But I don't think so.
"If United are really at it, which they will be, they'll win it comfortably. Even last year when United were slipping up, no team was strong enough to take advantage of it."
Chelsea, with new boss Andre Villas-Boas now at the helm, are seen by many as the biggest threat to United's dominance. But Keane feels otherwise.
"It's always the players down there, they all seem to self-destruct. They're big pals one minute and the next you hear they're all bickering with each other and players aren't happy if someone else scores."
Keane also gave short shrift to the hopes of Arsenal ("they haven't really bought anybody") and Liverpool ("in no position to win the league, nowhere near").
With those challengers dismissed, it's Roberto Mancini's City who are the only ones left standing as realistic rivals for the Red Devils in Keane's eyes.
"I don't think the current City group see United as a machine that can't be stopped," he said.
"Beating United at Wembley was a milestone for them. They've been close to getting results over United in the last few years.
"When a team is spending that sort of money and bringing in the quality they have, then they are a threat."
Source: Team Talk
Source: Team Talk