Chile drew 1-1 with Australia in the 2017 FIFA Confederations Cup on Sunday to qualify for the knockout stage from Group B.
James Troisi gave Australia a shock lead shortly before half-time, but Martin Rodriguez grabbed the equaliser after 67 minutes.
The Socceroos faded in the second half as Chile's quality finally trickled through after a quiet performance.
La Roja will play Portugal in the last four on Wednesday.
Australia freshened up its starting XI, making six replacements, including veteran Tim Cahill included. Chile also rang the changes, as they made five amendments to their side, drafting in Jose Fuenzalida and Francisco Silva in a 4-3-3.