Prop Paddy Ryan and uncapped winger Tom English have been added to the Wallabies Rugby Championship squad, with hamstring injuries set to rule out Laurie Weeks and Joe Tomane for the first two matches against New Zealand.
Both injuries are considered relatively minor, with Weeks and Tomane each expected to be out for two to three weeks.
However, that would be long enough to rule them out of the Rugby Championship and Bledisloe Cup games against New Zealand in Sydney next Saturday and in Auckland the following weekend.
"It's disappointing to lose Laurie and Joe at this point," Wallabies coach Ewen McKenzie said.
"But as has been consistent with our stance on injuries over the past year, we're going to continue to take a pragmatic approach and give guys with issues the chance to focus solely on their rehab before rejoining the squad.
"We don't expect them to miss more than a couple of weeks, and when they become available for selection once again, we'll know they are healthy and ready to contribute.
"As it is with sport, injuries provide an opportunity for other guys to come through, and I'm sure Paddy and Tom are both excited about taking part in our preparations for the All Blacks."
Ryan, who won a third test cap against France in June, comes in for Rebels prop Weeks, who aggravated an existing hamstring problem at training on Friday.
Weeks, who won his first two test caps coming off the bench against France, was drafted into the squad last Wednesday, after Scott Sio was ruled out with an ankle injury.
Ryan was called up ahead of veteran Waratahs teammate and loosehead prop Benn Robinson.
McKenzie emphasised he was looking more at the tighthead side.
"It's no secret we're trying to build more depth at tighthead prop and the upcoming fortnight will be a good chance for Paddy to continue improving at this level," he said.
Rebels winger English, 23, comes in for luckless Brumbies flyer Tomane, who missed the three-test series against France with a cheekbone injury.
Australian sevens representative English was one of four additional training squad members for the June three-test series against France.
"Tom is a guy we are continually learning more about," McKenzie said, "and is someone who impressed us with his attitude and abilities at training during the June series, along with being a consistent performer for the Rebels throughout the year."