"We knew Australia were never going to make it easy for us and they've made it tough for us for sure. We're very disappointed because we didn't feel in control of the game.
"We were ahead at the break and managed to get six points clear, which is a horrible margin because one converted try and you're behind. We were too loose and gave them opportunities to build a platform from which to get the score."
O'Driscoll, who won his 132nd Test cap at the Etihad Stadium, will feel a sense of déjà vu if he plays in Sydney because 12 years ago he was in exactly the same situation with Martin Johnson's 2001 Lions afte the Wallabies levelled the series in Melbourne.
"It's a huge challenge and the momentum from this game is now with them. But we won't let that phase us, we have to dig deep into our inner belief that if we were good enough to beat them once, there's no reason we can't do it again if we get our game right," said O'Driscoll.
"We were loose and gave them counter-attacking options. We just weren't able to close it out and didn't build phases.
"We spoke before the game that we still had a lot more to show and I still don't think we have shown a lot."