Old Trafford hero believes his former side can win every game left...
The Ipswich manager reckons the spirit in United's camp is unrivalled, with Chelsea showing frailties, leaving only Arsenal in Sir Alex Ferguson's way of a 12th Premier League title.
"United could win every game to the end of the season without any doubt," Keane told Sky Sports.
"They are fresh, they've got good balance, great experience and top players. See Chelsea yesterday [against Blackburn], they talk about the spirit in their camp and I'm not so sure.
"I think the biggest danger to United without a doubt is Arsenal."
Keane believes United's attitude is key to their success, something that is lacking in many of the Red Devil's rivals.
"I hear all the players and all the managers talking about spirit and character. Just look at United they way they handle victories and defeats — they are the best in the world at it," he said.
"You see other teams, they are get a good result and they are taking their tops off and hugging each other. The following week and they are fighting one another.
"United are the prime example of what a good spirit is about, and that is again because of the good characters."
With Arsene Wenger's Arsenal side only two points behind United with not long left in the season, Keane believes the Gunners have a chance to spoil the party at Old Trafford - depending on how they react to the two Champions League games against Barcelona.
"I think what will depend on it is how Arsenal will react, both physically and mentally, to both games against Barcelona," he said.
"It's the Champions League games that might take a little out of them. That is the big test for them.
"If it was just about league games left, I'd probably put my money on Arsenal. But with the Champions League we will see what that takes out of them."
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