Despite Manchester City's runaway lead, Ferguson has urged United to keep "believing".
He told MUTV, "With perseverance you never know what happens in football.
"I remember when Newcastle were 12 or 13 points ahead of us, we caught them [in 1996]. The year we were nine points ahead of Arsenal and had all the injuries and lost it to them [in 19980, when they beat us here 1-0.
"So things can happen you maybe don't expect to, but they can happen!"