"The reality of rugby is that most players get an opportunity at the misfortune of one of their teammates, but it's about what each individual does with that opportunity that counts the most," coach Ewen McKenzie said.
"That doesn't just apply to Peter but to a number of guys who are receiving a chance this week. There is no better way to make your mark than by playing well against the All Blacks."
Regular Wallabies this season, Christian Lealiifano and Scott Fardy are other injury casualties as the Wallabies arrive with some confidence, after their last big win against the Pumas, that they can ruffle the All Blacks.
Genia has his Reds teammate Quade Cooper as his starting five eighth for the first time out of three meetings this season with the All Blacks, while Matt Toomua pushes out a spot to replace Lealiifano who has an ankle injury.
While Genia and Cooper have produced strong form this year at Super 15 level, they have delivered mixed performances at test level. Cooper has been a slow work in progress while Genia seemed to flatten out after the Lions series.
"He has an incredible drive to see Australia succeed at this level and you'll no doubt see that in his performance against the All Blacks on Saturday night," coach Ewen McKenzie said.
The Wallabies lost 47-29 in Sydney and then 27-16 in Wellington to the All Blacks at the start of the Rugby Championship, but the coach said the chance to halt the All Blacks winning their 30th consecutive test on home soil was a great incentive for this match.
"History indicates that playing the All Blacks is a significant challenge, but you want to be measuring yourself against the best performing teams in the world and we are very much looking forward to that.
"It was pleasing to see us take a step in the right direction against Argentina, but the test for us now is to produce that form week-in and week-out," said McKenzie.
"At this level you need to back-up, play consistently and find solutions to win every game, which has been a large focus for us heading into this match."