Last weekend's 16-15 win by the Qantas Wallabies in Melbourne squared the series at 1-1 and who ever comes out on to at the ANZ Stadium this weekend will carry off the Tom Richards Trophy. Australia won in 12 years ago and O'Driscoll has been waiting ever since then to pay them back for ruining his first Lions tour.
"The general message is that it's still all to play for. They have been two incredibly keenly contested games. Both of them should probably have gone the other way that they did, and it now culminates with a winner takes all on Saturday.
"We knew we were never going to get it easy against Australia, and it has been proved. Yes, there is disappointment and you have to have a little bit of a mourning period after any loss, but the spirits of the guys have been picked up.
"It is important to be able to feel the disappointment because if you try to banish it immediately it will come back to you, and it still does at times throughout the day. You kind of think how scenarios could be different, having a series in the bag rather than one still to go and fight for.
"But then after a couple of days you just have to have the ability to shelve it and focus on the target. One more 80 minutes this season is all that is asked of everyone in the squad - the 80 minutes of their lives."
The Wallabies made a miraculous recovery in Melbourne in 2001 to level the series, beating the Lions by a record 35-14 margin after trailing at half-time, and 12 years on it was a 76th minute try from Adam Ashley-Cooper that hauled them back from the brink of going 2-0 behind and losing their grip on the trophy.
This time, though, there was only one point between the two sides and the small matter of three points separated the two teams over the first two Tests. So who will have the upper hand going into the decider in Sydney.
"People talk about the momentum going with the team that wins the second Test, and I would have agreed with it in 2001 because it was a comfortable victory they had back then. But just the way the two games have gone, with two points in the first one and one point in the second, just shows how tight it is between us," said O'Driscoll.
"I think the team that turns up on Saturday and gets some momentum from early on in the game will get the upper hand. I wouldn't go and say there is anything particularly we did 12 years ago.
"Just make sure you don't do too much training that week. There is a lot in the bank already, so just try to get the detail right and then save the energy for the pitch.
"I don't think there is a huge amount new we are going to learn about ourselves or about the opposition at this stage, so it is just about trying to be clinical when we do get the opportunity to take the pitch."
O'Driscoll believes the four days the squad will spend in Noosa this week will benefit them as they prepare for one of the biggest games of their careers.
"You have to be able to switch off for 24-48 hours away from rugby, even on Lions tours. When the time kicks back in to getting back on the park and into team meetings and talk about rugby we will do exactly that," he said.
"I've been unbelievably impressed with the whole squad, the manner in which they have carried themselves. It's all for the betterment of the team, not about the individual. That is what I like about this squad - we are still pretty tight and we all want the common goal, irrespective of who is in that 23 and who are the lucky ones.
"There is always a mental toll in games of this magnitude. Thankfully, you do get seven days to try to get over one game and have the building process for the next one.
"You would hope that within a week you would be able to forget the negative parts to the game you played and think positively towards what you are going to do, and incorporate into your game plan, for the following week.
"This game is very much mental as much as it is physical, and all the more so when you play opposition three weeks in a row. Not become a chess game, but you definitely get to know each other an awful lot more and you are almost anticipating certain things to happen. There is an element of trying to out-think the opposition.
"It's very hard to keep a side out when they do build momentum and get possession and territory to keep them out indefinitely. They set out their intent when they had a penalty in front of the sticks that they wanted a try, they didn't want to be trying to kick penalties.
"Credit to them. It was what it was, and we just have to be able to look back, regroup, realise where we went wrong and try to plug those holes for next time."