Sir Alex Ferguson's men head to White Hart Lane on Sunday to face a shell-shocked Spurs, who are still recovering from last weekend's 5-2 thumping by arch-rivals Arsenal, a result that left them eight points adrift of second-placed United.
While Spurs manager Harry Redknapp has said finishing third would mark a successful season, striker Emmanuel Adebayor has refused to give up entirely on the title even though it is almost certainly a two-horse race between the Manchester clubs.
United have not lost to Spurs since May 2001 and Ferguson said maintaining that record could be the key to their season.
"It's going to be a massive game," the Scot told Inside United. "If we can survive that one, then we'll have a big, big chance of winning the league."
The champions have 61 points from 26 games and trail leaders Manchester City by two points. Roberto Mancini's side host second-from-bottom Bolton Wanderers on Saturday which gives them an excellent chance to go five points clear before United play.
Ferguson has already been thinking about April's trip to City, which could decide whether the Premier League trophy will be decorated with blue or red ribbons.
"I would rather go there on level points," he said. "But if we could go there within striking distance of being top of the league, I'd take it."
SHOW CHARACTER
Spurs, who will be without midfielder Scott Parker after his red card against Arsenal, could accuse Ferguson of jumping the gun with Adebayor believing a win for his side on Sunday would keep them in the hunt.
"If you want to be champions these games against the likes of Manchester United are the kind of games we have to be winning," he told Spurs TV Online.
"After losing 5-2 to Arsenal we can't ask for a bigger challenge than playing Manchester United, but we are looking forward to it... we just have to show personality and character and bounce back as quickly as possible."
Defeat for Spurs would give Arsenal and Chelsea the chance to gain ground in the race for Champions League berths.
The two top-four regulars have found themselves facing the prospect of one of them not qualifying for the elite European club competition as Spurs have led the London charge this term.
Both have 46 points, with Arsenal occupying fourth spot from Chelsea on goal difference.
Arsenal have a tricky fixture at Liverpool on Saturday against a side still celebrating ending a six-year trophy drought by winning the League Cup on Sunday but are on a high of their own following the victory over Spurs.
Arsene Wenger said his side were "alive more than anybody thought" and could still overtake their north London rivals to snatch automatic Champions League qualification if they can build on last weekend's performance.
Chelsea, who visit West Bromwich Albion on Saturday, have been in some sim
