"It's no secret both sides will be focusing on the first 20 minutes," he told a press conference as the build-up to the final between the two traditional foes began.
"It will be about who can execute with accuracy. We've talked about that this morning. We need to be extremely accurate and be able to apply pressure at the same time.
"But the Boks will also be coming out and wanting to start well, so we'll prepare for that too."
The two meetings between the All Blacks and Springboks this year have been characterised by fast starts.
New Zealand blitzed their way to a 17-0 lead in the opening 12 minutes when they hosted South Africa in the Rugby Championship in Auckland in July and went onto a 35-20 victory.
When the teams met again at Twickenham in their World Cup warm-up match in late August, South Africa 14-0 up at halftime and extended their dominance after the break for a 35-7 record defeat of the Kiwis.
"We felt we were maybe a little bit superior, a little bit quicker in the first game and in the second game we were slow. We took a lot of learnings out of it," he added.
As for the All Blacks approach on Saturday, McLeod said their review of Friday's semi-final win over Argentina showed they needed to make better use of space presented to them.
"Argentina were extremely physical and we had to work hard to get through but there was also space available to us around that. The Springboks will be very similar, they put on a lot of pressure and come at you quite quickly," he added.
"We want to meet their big men running down hard, head on and be extremely accurate in the set-pieces. What's shown through the tournament is you need to be switched on for every single scrum."
McLeod said there would also be extra emphasis on dealing with the South African kicking game.
"We haven't encountered a lot of that in the tournament and we'll build on to this week. They're very good at getting up in the air and then getting the ball back," he added.
