London - South Africa and New Zealand will renew one of the greatest and most bitter rivalries in rugby in their World Cup semi-final at Twickenham on Saturday but off the field, the coaches and players remain firm friends.

For both nations, the game provides the ultimate challenge on a rugby pitch and in the adrenalin-pumping atmosphere of a high stakes showdown at such a prestigious venue, it promises to be another bruising battle.

However, behind the intensity and bone-crunching tackles is a mutual respect between the teams on the pitch that has in more recent years extended to solid friendships off it.

None more so than between the two coaches; New Zealand's Steve Hansen and South Africa's Heyneke Meyer.

"When you play teams you know really well and you've got a good relationship it brings a little bit more to it," Hansen told reporters.

"It's like playing your brother or your sister and you don't want to lose, particularly if you're the younger sibling.

"We really enjoy their company. They play hard on the track but they're good men off it. Heyneke drives that. He's the leader of their ship and I've got a lot of respect for him."

Meyer is equally fulsome in his praise of his All Blacks counterpart, who sent him a message of support after the Boks were stunned by Japan in their opening World Cup match.

"Steve is a quality man," Meyer said. "We are all under pressure. Only one coach will win it and the rest will probably be fired or will be under pressure in their countries.

"We've tried to bring the ethos back in rugby. Although we kill each other on the field, as coaches we can support each other."

New Zealand have a 59 percent win ratio against the Springboks over their past 90 meetings, impressive enough but comfortably their lowest against any nation.

They have beaten their other southern hemisphere rivals Australia 70 percent of the time and the average against all teams stands at an eye-popping 78 percent.

In World Cup matches, South Africa edge the head-to-head, including a famous 15-12 extra-time final victory in 1995.

Since then they have also beaten New Zealand to third place at the tournament in 1999 with a 22-18 success but were comfortably beaten 29-9 in the quarter-finals in Australia four years later.

More recently, the All Blacks have held sway, having won 10 of the last 12 meetings between the sides, including a 27-20 success at Ellis Park in July.