Ireland great reckons World Rugby will step in and stop Bok bench tactics

Rassie Erasmus and Jacques Nienaber have decided to go with a 7-1 split for Saturday's game, with flanker Kwagga Smith covering the backline if the Boks suffer more than one injury behind the scrum.

It has caused controversy, despite it being completely within the laws of the game, and Wood has been one of those dissenting voices.

"I think it will change after the World Cup, I don't think it will be allowed to happen going forward, but it's within the law, and I think it's playing to their strengths," he told the Off The Ball podcast.

"The idea of coming up with something novel is something he (Erasmus) has consistently done for the last period of time."

The Springboks first attempted a 7-1 split against the All Blacks, which proved to be successful as they claimed a 35-7 triumph in a World Cup warm-up.

Wood stated that it was "kind of frightening" when they changed seven of their pack against New Zealand.

"I don't know that it's necessarily fair. It works to the advantage of teams with huge forwards. They tend to be the only team that relies almost exclusively on that sense of having giants of men," he said.

"If you go back to the original view of the game, it's a game for all people and sizes and it's to try and have it so it is safe and fair.

"I think they may bring the number of subs down after the World Cup and I think it will look for a balance that fits rugby slightly differently than it does at the moment.

"It was a kind of frightening sight to see seven forward changes."

Wood did, however, praise Erasmus in his own inimitable way, stating that South Africa's director of rugby has a very astute rugby brain.

"I will say that Rassie is consistently excellent at deflection from a lot of different things," he added.

"I was talking to a group of South Africans a couple of weeks ago and I just said: 'He's never done anything novel, he's very boring, he doesn't think outside the box', and of course they reacted badly because they didn't understand sarcasm, which was quite entertaining.

"Everything that is done pushes whatever he can push."

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