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 largely dry day with just a risk of isolated showers especially in the north and west. Heavy and persistent rain overnight.
On a visit to Wales Labour leader Ed Miliband sets out a ten-point promise on how his party will deal with immigration.
One of the men was described as carrying an object similar to a handgun in the bakery delivery van hold-up