Ferguson: Beat Chelsea and title is ours
His side have dropped only two points at Old Trafford all season and are in good spirits after reaching the Champions League final this week with a 6-1 aggregate win over Schalke 04 which was completed using a second-string team.
Having rested key players, including striker Wayne Rooney, who has now recovered from a tight hamstring, Ferguson believes his team are in ideal shape for the huge Premier League game.
"If we win, I think we should win the league," Ferguson told a news conference on Friday.
"Our home record is fantastic, it's probably the best in Europe, and it has to be on Sunday, it's a big game."
With three games left, United have 73 points to Chelsea's 70, with both on the same goal difference, meaning the London side will go top if they win while a victory for United would leave them needing one more point to clinch the title.
United travel to Blackburn Rovers next week before hosting fellow strugglers Blackpool on the last day of the season in what on paper looks an easier run-in than Chelsea's home match against Newcastle United before a tricky trip to Everton.
"Our home form has been an advantage to us this season, that's the reason we're there because if you look at our away record it has not been great," said Ferguson, whose side have collected 24 points from a possible 54 on their travels.
United's 1-0 defeat at Arsenal and Chelsea's 2-1 win over Tottenham Hotspur last weekend has set up Sunday's game as key in the title race, a notion that looked unlikely two months ago when the champions trailed the leaders by 15 points.
The loss at Arsenal forced Ferguson into some drastic squad rotation against Schalke, making nine changes from the side that started the first leg, and he was glad his players will be as rested as the Chelsea side who did not play in midweek.
"That makes a difference at this time of the season," said Ferguson. "You've got two fresh teams and it should be a fantastic game."
Chelsea were the last side to win at Old Trafford, more than a year ago, and their late charge in a bid to retain their league crown owes much to March's victory over United at Stamford Bridge when they came from a goal down to win 2-1.
"The result against us was the change for them," said Ferguson. "That gave them that lift from being out of the game to winning it and, of course, us losing to Arsenal on Sunday is going to open the door for them."
Despite the slip-up against Carlo Ancelotti's side away from home, United can draw comfort from their more recent meetings with Chelsea in the Champions League where they beat them 3-1 on aggregate in the quarter-finals last month.
Ferguson said he expected striker Didier Drogba to start for Chelsea but had no idea whether record signing Fernando Torres would feature. He also gave little away about his own lineup, other than saying midfielder Darren Fletcher would not start.
Fletcher came on for the last 20 minutes against Schalke, getting a standing ovation after two months out with a virus, and Ferguson is hoping he will be back at his best in time for the May 28 Champions League final against Barcelona at Wembley.
"He has almost three weeks to the final and that is his target," he said. "If he does reach it, it would be a great boost to us. As we all know he is a big-game player."