"They [Wales] have a new approach," Fourie said ahead of the Boks' Rugby World Cup opener against the Welsh in Wellington on Sunday.
"They have a new defence system as well and they are rushing up quite quickly [in defence] and putting teams under pressure.
"They are also putting in a lot of hits in the rucks so we just need to stick to what's been working for us and do even better."
Fourie, making his third appearance at the global spectacle, believed the stiff competition in the Springboks' pool group could work in their favour.
"It is a very tough group and that will prepare us for the quarterfinals and going onwards," said the experienced Bok centre.
"It can be a positive. We've got Wales, we've got Fiji, Samoa, and not to throw away Namibia, and we are taking all four of those games very seriously."
The Boks have all sung the same chorus, insisting that Wales will be their only focus and that the other teams in their group will be studied closer to the actual matches.
Fourie said it would remain that way throughout the competition.
"That's how we want to approach this," he said.
"The first game is Wales and we want to come through that one convincingly and take it from there."
The Bok backline failed to score a try in their last seven matches, but that was of little concern to the man ranked third among the top try-scorers in the side's history.
"I don't think it is a concern. We've worked at what we've wanted to work on, and we've got the smaller details right, and I think we achieved that in our last game [against the All Blacks in Port Elizabeth].
"We just need to handle that rush defence, get quick ball and go forward."
The team had travelled well, according to Fourie and, although they were still recovering from jetlag, they were starting to settle into their sleeping routines.
"The way we arrived here was excellent; the people welcomed us with open arms so everything else is excellent."
Aside from training and media responsibilities, the Springboks had been given freedom to do whatever they wished - within set parameters - and Fourie felt the team were balanced in how they approached the build-up to their title defence.
"When we step onto the pitch we know what we want to do and when we step off we relax.
"It is a World Cup and a great occasion, so we need to take in as much as we can."