Toby Faletau has been ruled out of Wales' Australia tour after breaking his hand during Saturday's first Test defeat in Brisbane.
The Newport Gwent Dragons number eight will fly home to have his injury further assessed, with Wales caretaker coach Rob Howley calling up Melbourne Rebels' Gareth Delve from outside his original 34-man squad.
Former Gloucester captain Delve won the last of his 11 caps in 2010, and he was at the game in a radio commentary capacity.
Wing George North, meanwhile, will undergo intensive treatment on a haematoma to his thigh in a bid to get him fit for the second Test in Melbourne next Saturday.
North was forced off during the first half of Saturday's encounter, and he is crucial to Wales' hopes of squaring the series.
Howley has named his team for Tuesday's appointment with the Brumbies in Canberra, with lock Luke Charteris the only survivor from Brisbane.
Delve will be on the replacements' bench, where his colleagues include Ospreys lock Ian Evans, who arrived in Australia on Saturday night following his wedding in Greece.
Evans' Ospreys second-row partner Alun-Wyn Jones will captain the team, taking over from a rested Sam Warburton, while there is another opportunity for 19-year-old Cardiff Blues wing Harry Robinson.
Robinson lit up Wales' 30-21 victory over the Barbarians eight days ago by scoring a dazzling solo try, and he will look to impress on Tuesday, especially with North battling injury.
Howley said: "We are a game down, but we still have all to play for in this Test series and Tuesday night is the perfect opportunity for this squad of players to move on. We have one or two bumps and bruises, and we are expecting players to back-up after playing a tough Test match and go out there 72 hours later and play for their country."