In a rousing performance before 90,307 fans at the Melbourne Cricket Ground, the tourists responded spectacularly after slumping 23-5 down, with Hugo Keenan’s 79th-minute try claiming a famous win.
It was a sensational reply after being stunned by three tries in eight first-half minutes from Australia’s James Slipper, Jake Gordon and Tom Wright.
The wounded Lions clawed back to be 23-17 behind at the break, then dealt Australia a crushing blow with Keenan’s match-winning heroics.
It is the first time since 1997 that the Lions have wrapped up a Test series with a game to spare after winning in Brisbane 27-19, and not since 1966 have they managed the feat against Australia.
They remain unbeaten after eight tour games in Australia with only the final dead rubber Test in Sydney next weekend standing between them and a whitewash.
Coach Andy Farrell touted the showdown as the biggest of his players’ lives, and they rose to the occasion, but it was a titanic battle against a vastly improved Australia.
The hosts beefed up with marauding powerhouse forwards Will Skelton, Rob Valetini and Dave Porecki all back from injury and their presence was huge – helping combat the brutality that helped the Lions win in Brisbane.
In Australia’s past two series against the Lions, in 2001 and 2013, the Wallabies lost the first Test, then levelled both in Melbourne.
And they started well when Tom Lynagh nailed a penalty on three minutes to settle their nerves, then made it 6-0 soon after when he slotted another from 40 metres.
The Lions, though, grew in confidence and began laying siege to the Wallabies’ line, with Ireland hooker Dan Sheehan diving over two tackles to dot down and open their account.
Undeterred, the hosts kept coming and veteran prop Slipper powered over for a converted try with the Lions’ problems compounded with Tommy Freeman sent to the sin bin after repeated infringements at the breakdown.
It proved costly, with the Wallabies grabbing two tries in his absence, the first to scrum-half Gordon, who sniped through a gap, then fullback Wright after a sizzling run from Joseph-Aukuso Suaalii.
With Freeman back on the field, the Lions regrouped and clawed back with two tries of their own in quick succession.
England flanker Tom Curry snared the first after being fed by Jamison Gibson-Park on the wing, with centre Huw Jones forcing his way over for the second.
In a setback, Valetini failed to return for the second half, and Skelton went off soon after the restart.
Tate McDermott converted a penalty to increase the hosts’ buffer, but the loss of their two big forwards was felt, and the Lions began gaining ascendancy.
Ireland lock Tadhg Beirne crossed in the corner, and with Finn Russell adding the extras, the Lions were only two points adrift with 20 minutes to play.
In a frantic finish, the Lions kept pressing with Keenan scrambling over at the death to send the visiting fans into raptures. (AFP)