South Africa captain Jean de Villiers believes the unity within Heyneke Meyer's squad puts them in with a chance of lifting the Rugby World Cup.

De Villiers' side are among the favourites to lift the Webb Ellis trophy on October 31 and add a third title to the ones they lifted in 1995 and 2007.

The Springboks open their campaign against Japan in Pool B on Saturday with the two-time champions expected to make a winning start, and De Villiers goes into the clash pleased with their preparations.

"It's a special bunch of people, I've said it many times before," he said. "They're not just good rugby players, they're good people.

"So a lot of friendships have been built over the last four years and it's nice to be able to go into battle with guys that you enjoy spending time with.

"So the vibe has been really good, the attitude at training this week. Whether it was raining, whether there was sunshine, whether we had to take our shirts off to train in the rain or not, the guys were just committed to the cause.

"I think every guy that is in the 31-man squad appreciates the fact that not everyone gets an opportunity to play in a World Cup and we want to make the most of that opportunity whenever it comes your way.

"We're excited about the challenge that lies ahead. We know that it will be a fierce battle and for us [against Japan] it's just being able to do the country proud whenever we put that green jersey on."