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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FIFA has opened proceedings against Neil Taylor following the Wales defender's challenge on Republic of Ireland defender Seamus Coleman,
A nesting platform and perching post has been installed at WWT Llanelli Wetland Centre in the hopes of attracting ospreys to the Bury Inlet.
West will fare the worst today with strong winds and heavy showers. Elsewhere it will remain dry with warm spells of sunshine.