The Springbok's emphatic win at Twickenham was not only the heaviest defeat the All Blacks had suffered but came on the back of a powerful forward display, with South Africa sparking controversy by naming seven forwards out of possible eight replacements and then overwhelming the Kiwis.
But Smith was quick to remind of the numerical advantage the Boks enjoyed for much of the match after Kiwi lock Scott Barrett was sent off in the first half.
"They got a red card at Twickenham and went down to 14 men. This weekend is the one that counts. So, we're really looking forward to it and we know it's going to be an epic battle. Upfront with the forwards it's going to be physical but we're excited for that. It's a great challenge," he told a press conference.
It is for a second successive time that the South Africans find themselves in the build-up week before a World Cup final, having won in Japan four years ago.
"I think the coaching staff tried to keep everything the same but obviously there's a bit more pressure this week, but we tried to focus on process and train the same as we have been training before," Smith added.
The 30-year-old Smith is again expected to be named among the replacements, even if South Africa are unlikely to again pick a seven-one split among the forwards and backs on the replacements' bench when they announce their team on Thursday.
"If you look at our bench, even back in 2019, it has had a massive impact for the Springboks," he said.
The fabled 'bomb squad' have a proven ability to come and change the outcome of games, as was the case last weekend as the Boks came from behind to edge England in their semi-final.
"For us, when we are on the bench, we know we've got a massive responsibility to fulfil. The nice thing is for us is that we can watch the first half and see where we could be falling short as Springboks," Smith added.
"We then know what our job is when we go onto the field and we can rectify that. You've got to be ready and make sure that you use your opportunity when you get it."