O'Connor has played just one previous Test at 10 - against Wales in 2011 - and his selection in the position for Saturday's series opener at Suncorp Stadium by coach Robbie Deans is a significant gamble. But the versatile 22-year-old, who will be winning his 38th cap, insists he is ready to prove Deans' judgement is sound.
"Growing up I played my rugby at 10. The 10 is not normally the biggest guy on the field and that's probably the point where everyone attacks," he said.
"I've been used to that all my life. I can't express how pumped I am - I just want to get out there. I've been watching the Lions tour over the last few weeks and it's made everyone hungry. It's a huge occasion and I'm looking forward to it - the shoulders are ready.
"The Lions have brought their A game but there's some good support around me in guys who can really control the game. You can build combinations on the training field and we've been doing that. I feel very confident over how it's been going."
Some of the playmaking burden will be lifted by the presence of debutant and in-form Brumbie Christian Lealiifano at inside centre. With Kurtley Beale deemed unready to start against the Lions following his return from alcohol-related problems - he is named on the bench - Berrick Barnes has been selected at full-back.
"Kurtley was close to the starting XV, but just being in this position is a good achievement for him," Deans said. "He's got himself right back there in every way, physically and mentally. If there's an early injury, there would be no qualms over him coming on."
Completing the trio of new caps are wing Israel Folau, who this time last year was playing Australian rules football following a switch from rugby league, and blindside flanker Ben Mowen. The Lions, battle hardened by six provincial matches, are hoping to capitalise on the fact their opponents enter the series without having played a warm-up match.
"We've made the most of the time we've had and I can assure you we'll hit the ground running. The players know what's coming," Deans said
"We've tapped into the past and prepared as best we can. We can't do any more without playing, to be frank. The Lions have been building their game and have played very well. It will be a tough Test, but we'll bring a fair amount to that. It's going to be an epic occasion."