Coach Michael Cheika on Thursday named the pair along with back-rower Pete Samu, who is poised to make his first international start off the replacements bench.It caps a remarkable rise for Paenga-Amosa, who was playing club rugby in Sydney this time last year.
Timu switched from rugby league, where he played for the Brisbane Broncos in 2017, before suffering a serious knee injury in his first training session with the Queensland Reds.He partners David Pocock, who will play at blindside flanker for the first time for Australia in his first Test appearance since December 2016 after taking a sabbatical.
The Wallabies include playmaking stars Will Genia, Bernard Foley and Kurtley Beale while winger Dane Haylett-Petty is making his first start in almost nine months after a biceps injury. Samu Kerevi's shift to outside-centre squeezes Tevita Kuridrani out of the 23-strong match squad and it will be Kerevi's first start at No.13 since last year's Test against Japan.
Izack Rodda will pack down alongside Adam Coleman in the second row, with Sekope Kepu earning the nod over Taniela Tupou at tighthead prop. Cheika also confirmed a six-two forwards-backs split for the reserves that includes Australian-born Samu, who was the subject of a recent trans-Tasman tug-of-war between Australia and New Zealand.
Allan Alaalatoa will revert to loosehead prop on the bench to allow room for tighthead Tupou to potentially play his first Test at home. Ireland have won three of the last four meetings between the two sides but the Wallabies won their last game in Brisbane 22-15 in 2010.
Australia: Israel Folau; Marika Koroibete, Samu Kerevi, Kurtley Beale, Dane Haylett-Petty; Bernard Foley, Will Genia; Caleb Timu, Michael Hooper (capt), David Pocock; Adam Coleman, Izack Rodda; Sekope Kepu, Brandon Paenga-Amosa, Scott Sio.
Reserves: Tolu Latu, Allan Alaalatoa, Taniela Tupou, Rob Simmons, Lukhan Tui, Pete Samu, Nick Phipps, Reece Hodge.