http://uk.reuters.com/article/idUKTOE65F03720100616Polota-Nau aggravated an ankle injury after coming on as tighthead prop for the Australian Barbarians in Tuesday's 15-9 loss to the tourists and will miss the second test, local media reported on Wednesday.
Australia beat England 27-17 in Perth last weekend but an inexperienced Wallabies front row were battered in the scrum by a dominant English pack.
Australian selectors have few alternatives available with first-choice props Ben Alexander and Benn Robinson out and hooker Stephen Moore also still injured.
Props Salesi Ma'afu and Ben Daley could once again start alongside hooker Saia Fainga'a in Sydney at the weekend.
Forwards coach Jim Williams admitted the home side must be more physical to match the English pack.
"It's just got to be ramped up again this week. The physicality of the England team, especially in their tight play was enormous," Williams told AAP.
"The physicality that these guys play in the English Premiership and the Six Nations is just relentless and we need to make sure that we meet that battle head on."
Fuck.