The International Rugby Board has admitted their officials were in the wrong when the Wallabies were prevented from using a fresh replacement and reduced to 14 men at the end of last weekend’s thumping by South Africa.

The IRB on Wednesday confirmed Irish referee Alain Roland erred in stopping reserve hooker Saia Faingaa from replacing an injured Tatafu Polota-Nau with 14 minutes left in the 31-8 loss at Pretoria.

Roland claimed Australia had already made their maximum seven permitted substitutions after coach Robbie Deans had rotated his props around during the match, with Benn Robinson replaced early and then returning late to take Ben Alexander’s place.

A glum-faced Faingaa was forced to watch the rest of the match from the sidelines alongside Polota-Nau (shoulder), continuing what were farcical scenes.

“This was an unfortunate case of human error by the match officials who fully recognise and accept that they made a mistake in the application of the substitution law,” said IRB match official selection committee chairman John Jeffrey.

The IRB’s admission has ensured Deans has saved some face but it will be interesting to see whether he continues the practice of rotating his props on Saturday night against Argentina.

James Slipper, who trained with the starting 15 on Tuesday, is expected to be named at loose-head in place of Robinson when the team is named on Thursday afternoon.

Under the game’s laws, a substituted player may only replace a front-rower when he’s injured, sin-binned or sent off.

But, highlighting the grey area of the law, Australia have made a habit of tactically sharing the load on their three props without injuries being incurred.

While not renowned as strong in scrummaging as Robinson, Slipper has shown himself to be fitter around the park and could play longer game time before a traditional second-half replacement is made.