Irrespective of the outcome of the Stadium of Light showdown against the Foxes, Allardyce knows the clash at Carrow Road is the one most likely to determine whether the Black Cats can prepare for another top-flight campaign next season.
But he maintains confidence is high among his players that they can take a step closer to realising that aim by becoming only the fourth team to beat Claudio Ranieri's buoyant side in the league this season.
Allardyce said: "We need to go out and win this game but at the end it's still about not losing it
Norwich will be must-win for us because they are our nearest rivals and we will have to go all out to get the three points."
Allardyce is unsurprisingly determined to put a positive spin on his side's plight which has seen them fail to win any of their last five Premier League games - but remain unbeaten through the last four of them.
And while missed opportunities cost his side dear in last week's frustrating goalless draw against West Brom, Allardyce is convinced his players are showing enough fight and belief to make victory over Ranieri's men eminently possible.
"If we're going to beat them we can't afford to miss the sort of chances we missed last week and Southampton missed (against Leicester) last week," added Allardyce.
"When we watched it back it was even more difficult to take
It was a great shame that it was not a very comfortable victory but you have got to take your chances and if you don't you pay the price in this league."
Allardyce, who expects to pick from a fully fit squad with the exception of knee injury victim Duncan Watmore, hailed his opposite number Ranieri whom he believes is enjoying the best period of his long and illustrious coaching career.
"He's got a huge amount of experience and he's been absolutely fantastic - a breath of fresh air," added Allardyce.
"I'm sure he's enjoyed every minute of this season perhaps more than any other job he's had, because I don't think his expectations would have been so great."
What has particularly impressed Allardyce is the way Ranieri has adapted his previously attacking tactics to become resolute at the back as the improbable title dream looms ever closer.
"They were much more open and counter-attacking which brought them lots of goals, and then they mastered the way the opposition tried to combat that by dropping deep and not allowing them space.
"But they've still managed to break down the opposition for the all-important 1-0s - that's why they're at the top.
"But we are confident in the way we are performing and we just have to do that little bit extra like Leicester have been doing in order to get the win."
Source : PA
Source: PA