Australian fly-half James O'Connor finished a jinking run with a try in the very last play of the first half, to narrow the scoreline to 19-10.
The Lions lead at the break thanks to Alex Corbisiero's early try, and 14 points from the boot of Leigh Halfpenny.
Australia could have been ahead, but turned down five opportunities to kick penalties for goal in the first period.
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Crowds came to hear him speak this afternoon in Bangor - a seat where fewer than 100 votes could make the difference at the next election.
Scattered showers with the odd heavy burst possible but there will be plenty of sunny spells too.
A rather wet and windy evening, with rain in the north and showers elsewhere.