Matfield, who was also named the official vice-captain for the season, predicted a top-class physical forward battle with Italy on Saturday.
While a depleted Azzurri team are not expected to put up too much of a fight in South Africa, Matfield believes otherwise.
"They put a lot of passion into their game," said Matfield.
"They love the tight phases and they love to maul. It's going to be a big battle for us up front."
De Villiers laughed off suggestions that a long discussion had been required to decide on his captain, calling Matfield a "genius" and making it clear he was the favourite for the leadership role.
"I didn't decide anything, he has earned it," De Villiers said.
"He truly is in a league of his own. The way he analyses the game, reads the game and works with people involved made the choice no choice at all.
"I wanted to do what was right for rugby. I must also announce that whenever John Smit is unavailable, Victor will lead the team."
"We are looking at this as just another Test, but one that is important with the Tri-Nations just two weeks away," he said.
"We have standards to live up to and certain things we still want to achieve.
"If we see an opportunity this weekend we'll take it. We won't go the conservative route. Coming from the north we do tend to be a bit more conservative.
"But we have chatted about it, and even though it will be a challenge, this weekend will provide us with another opportunity to see what works for us ahead of the Tri-Nations."
The match will pit the Springboks against former coach Nick Mallett and De Villiers revealed his respect for the 51-year-old tactician.
"We respect Nick and how he has taken up the challenge of turning Italy around," he said.
"But we've also got a job to do. One of their big strengths is the strength of their forwards, and having Nick involved has obviously reiterated that. They don't have a lot of weaknesses.
"But we can't concentrate on their strengths and weaknesses, we need to concentrate on our own strengths and weaknesses."