Welsh centre Jamie Roberts - facing Australia for the first time this summer due to injury - has scored the Lions' fourth try, taking a pass from replacement Conor Murray before galloping home.
Halfpenny makes it another seven points, and the Lions start to celebrate a series win.
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A fairly grey and cloudy start with showers. Improving during the morning with sunny spells developing and showers becoming isolated.
There are calls for deradicalisation programmes in Wales after three men were jailed for helping a Cardiff teenager join ISIS.
Clear skies will continue for a time allowing temperatures to drop to freezing in many places. Cloud developing during the early hours.