Heading into the decider all-square, it was anyone's game - indeed after the Wallabies had won the previous clash the hosts could be forgiven for a bullish attitude.
They were, however, quickly brought back down to earth as England prop Corbisiero kicked off a mammoth performance with an opening-minute score.
Jonathan Sexton and George North each added tries before Roberts completed the rout, the Lions running out 41-16 winners to kick off the celebrations among the red army.
"It's a pretty indescribable feeling," said Alun Wyn Jones, skipper on the day. "We represented the four countries with pride."
The lock had taken over the role from Wales teammate and tour captain Sam Warburton, after he was ruled out of the third Test with injury - but the flanker was on hand to join the party.
"It's been an immense Test series," said Warburton. "To our boys, a massive well done. We worked hard for this. To the fans, who spent thousands of pounds to come here, you've made our tour."
It was the Lions' first series triumph in 16 years and saw the likes of player-of-the-series Leigh Halfpenny elevated to rugby's upper echelons.
Players, coaches and fans alike revelled in the result that night in Sydney and have done throughout the intervening two years.
However, attentions have also turned to the Lions' next challenge - a 2017 trip to New Zealand.
It will no doubt be one of the toughest tests ever faced by a touring Lions side, with the All Blacks boasting a phenomenal recent record and heading into this year's World Cup as favourites.
But those who tasted victory 730 days ago know what it takes to triumph in that red shirt and they will have some exciting new faces by their side.
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