A try from fly-half Jonathan Sexton - and another Leigh Halfpenny conversion - put the Lions clear again heading into the final quarter.
Sexton touched down after receiving the final pass from Halfpenny in a slick Lions move in the left corner.
Australia had closed the gap to just three points early in the second half through two Christian Leali'ifano penalties.
Halfpenny added another penalty of his own.
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A glorious end to the week, with sunshine which may turn a little hazy later! Temperatures will peak today!
A dry night with incredibly mild temperatures. Setting us up for another lovely day tomorrow!