And despite having nearly 57,000 people watching inside the Etihad Stadium and millions more glued to the televisions worldwide, Lealiifano insists his focus was on kicking in his backyard with his nephews rather than on keeping the series alive for his side.
"Sitting back now and thinking about it, it was a massive occasion. But it was just going through the same process I go through when I'm kicking at practice," said Lealiifano.
"I remember a while ago asking Stirlo, Stirling Mortlock, 'what do you think about when you kick?' He told me his process and said 'that's all you need to think about'. I've taken that approach into my kicking. He just said he looks beyond the posts, that's his target and he focusses on kicking it in that area. For me I was like, 'it's pretty simple, so alright!'
"That's what it felt like. I was just trying to block it all out and think like that - 'you're just in the backyard mucking around with your nephews,' because they put me under more pressure than what I felt! They'd probably put me off!
"You're obviously aware of what's happening and I found it really hard to hear myself think because the crowd was so crazy. I just had to zone in to what I do normally and thankfully I did that."
It was a remarkable comeback for the 25-year-old inside centre given that he was knocked unconscious just 50 seconds into his international debut in last week's first Test.
Lealiifano suffered a sickening blow when he attempted to tackle Jonathan Davies immediately after the kick off in Brisbane but he somehow managed to put all that behind him to become his country's hero in Test number two.
And the turnaround in fortunes was even more significant in that it followed on from a lengthy spell on the sidelines with a broken ankle last season, a setback that many predicted might rob him of a Test career altogether.
"I feel it's a massive reward for not only myself but also for my friends and family and team mates who have stuck by me through those tough times. It's a very humbling feeling to know what I've been through and to have my family here in Melbourne was amazing. I'm just very grateful," added Lealiifano.
"It was (a tough week) because I couldn't contribute to the side. When the minute went past I was giving myself a little fist pump that I'd made it past the minute! As soon as I got past the minute I was like 'this is what playing Test match footy is like!' After that it was just back to work as usual and trying to do my best for the side.
"That match was the hardest match I've played in so far. Their defence was very, very good so we'll go away and look at areas we can target. It was Test-match footy and both sides wouldn't give an inch. You've just got to try and find opportunities where you can, but it was very tough.
"We came here with the mentality that it was all on the line and it's the same for next week. It's do or die. Whoever wins takes the cup."