The series climaxes in a winner-takes-all final Test at Sydney's ANZ Stadium with the Lions one victory away from a first triumphant tour in 16 years. Assistant coach Rowntree outlined what will be required to topple the Wallabies, who enter what is expected to be another epic struggle as marginal favourites.
"Seeing how we've trained all week, crikey we're ready for this battle," Rowntree said. "We saw the reaction from Australia after they beat us last weekend - their captain James Horwill was crying. They threw everything at us and beat us by a point. We didn't get our game going and we know that."
He added: "There's loads more to come from us and the guys are desperate to win. This is grand final rugby, the last throw of the dice with everything to play for. There's one huge performance left in us. These players are desperate for tomorrow.
"We have to go out and give it everything. This is the biggest game of our lives, as players and coaches. A lot of us have been involved in grand final games, but this is the biggest one for us."
The Lions face an Australia team containing 110-Test veteran George Smith, who returns for his first international since 2009 in place of Michael Hooper.
The 32-year-old openside, the only surviving Wallaby from the 2001 series, has been in outstanding form for the Brumbies and only missed the first two Tests due to a knee injury six weeks ago.
"I'm surprised by his selection. He's been out for a long time and it will be interesting to see his match fitness," Rowntree said.
"They've got three good sevens in that squad and from what we've seen of him in the Super 15 is that he makes good decisions.
"He's still very good technically and makes good decisions on when to go into the breakdown. It will be a big challenge for Sean O'Brien. I'm hoping his selection is a reflection of what we brought to the breakdown."
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