South Africa coach Heyneke Meyer hopes his team's shock loss to Japan was the wake-up call they needed early at the Rugby World Cup.

The Springboks suffered a 34-32 defeat to Japan in Brighton in their opening game of the showpiece event on Saturday.

Meyer is desperate for his team to respond to the loss in Pool B, with their next outing a clash against Samoa on September 26.

"This will be a very big wake-up call for us. Again, Samoa isn't an easy team, Scotland and America as well. There's no easy games," he told a news conference.

"If this isn't a wake-up call, nothing will be a wake-up call, but it's going to be tough, every game is tough and I've said before the World Cup, this is going to be the toughest World Cup ever so I think there'll be more shock results.

"I don't want to take anything away from Japan. They deserved it, they outplayed us, but we have to pull together, it's not good enough and we have to go through.

"Myself as a coach has to take responsibility and push the right buttons to get us right on track and the players as well.

"It's just not good enough, we have to go through to the next round and it's going to take a huge effort on and off the field."

A late Karne Hesketh try saw Japan to the famous victory, which was just their second ever at the World Cup and first since 1991.

Springboks captain Jean De Villiers said his team were well below their best and struggled to explain what went wrong.

"I think this is just one of those performances where we can't really put our finger on why we lost, but we were beaten by a better team on the day," he said.

"I think credit should go to Japan and the way they played. They stuck it out until the end and as players we need to take responsibility and ownership for this performance because it's way below par for us and the standards that we set ourselves.

"It really is difficult to say where it went wrong, but in saying that, it wasn't good enough by a long shot."