Belief can be a powerful emotion. Eddie Jones sure hopes so. His men will need to extract every ounce, and even then it might not be enough to get past the well-rested, highly motivated All Blacks at Twickenham.
How different this week could have been for England. Had the Springboks embraced a smidgen more clinical finishing; had referee Angus Gardner gone the other way on Owen Farrell's controversial tackle at the death, had Handre Pollard knocked over his late penalty attempt, England would be under siege – Jones edging closer to the chopping block.
Fine margins indeed.
One point the difference in the end, Jones savoured the precarious positive vibes his squad is now embracing, following two wins from their past seven tests, as he extolled the benefits of the narrowest of victories gained solely through penalties.
While England's players offered more measured thoughts about the All Blacks, Jones resembled a miniature cat on hot tiles such was the enthusiasm he attempted to project.
"I didn't need this to make me believe we can beat the All Blacks I thought we'd beat the All Blacks back in 2016 so nothing has changed, mate," Jones said, reflecting back to the start of his turbulent tenure.
"I said to the boys after the game I can't wait. They are the benchmark in world rugby. They are who you want to play against. Where you are in the world you only know when you've played against the All Blacks. Any team that wins 91 per cent of their games is a great team. What other teams in world sport do that?"
Jones knows that challenge firsthand. Once a 70kg hooker, he recalls opposing All Blacks great Sean Fitzpatrick with Sydney club Randwick in 1988 - "you can find anything on YouTube these days" – alongside Wallabies coach Michael Cheika, and their respectable 25-9 defeat.
"We had the smallest losing margin of any team on tour, including Australia, because we believed we could beat them."
The following week, Jones was on the receiving end of a 50-0 thrashing with New South Wales.
"No one in that side believed. You've got to believe you can beat them. You've got to understand where they are weak, where they are strong, and you've got to be disciplined about your game plan."
Jones, then, would be pleased to hear messages emanating from England's Lions contingent, the likes of world-class first five-eighth Farrell and midfielder Ben Te'o who may draw on experiences from their second test victory in Wellington last year.
"Course we believe, anyone can be beaten," Farrell said. "I don't think any team is unbeatable. I'm sure people will talk about all different sorts of things this week but we've got to get better and that shows on the pitch.
"They're a very good team with some very good players and obviously they've got belief in what they do because they stick in games for a long time and normally come away with a win.
"We've moved a long way since 2017, and I'm sure they've moved on too. We've got to look a bit more recent. The main thing is we get excited for what's coming but at the same time we're ready for anything. We've got to go in with clear heads and see what's in-front of us.
"We know it's going to be a big test."
Te'o, the former South Sydney Rabbitohs and Queensland back-rower who will rekindle his battle with Sonny Bill Williams, is ready to embrace the occasion, one that's been three years in the making.
"If you're saying am I daunted by it? No I'm not," Te'o said. "I've played them before and I'm looking forward to doing it again and I'm sure they're looking forward to playing us.
"Mainly the fans have been looking forward to this game for a long time. We were going really well and it was built up, you know, this one v two type thing. It's been a tough period for us but this is the type of test we need to see where we are at."
Jones at least appreciates the full-strength All Blacks are a completely different beast to the Boks, who, other than Damian de Allende, largely adopted a limited, direct approach to attack.
Jones predicted Steve Hansen's men will be keen to run from everywhere, and put the ball in the air, but might also be wise to note the All Blacks' set piece strengths.
With England's injury issues, particularly in the loose forwards and loose head prop, and their major struggles at the scrum and defending the Boks' rolling maul, the All Blacks may opt to target Jones' heavily-depleted pack before unleashing threats wider out.
The All Blacks, having given the vast majority of their first-choice 23 last week off, have the advantage of beginning preparations in much better physical shape, too.
Jones can flay his claws all he likes but he will, therefore, need to concoct something special if England are to deliver on belief. That alone is unlikely to be enough.