It was that race which cost Brown a perfect 27-from-27 finishes.
Struck by illness, Brown pulled out of the Hawaiian race on the cycle leg - his first 'did not finish'.
He took a break and pitched himself into what he hopes has been a perfect build-up for tomorrow's race and his return to Hawaii.
He is well aware that this will be no stroll in the park with last years runner-up Luke Bell and rising Kiwi star Kieran Doe both serious threats.
The dreadlocked Doe beat Brown in January's Tauranga half marathon and goes into his biggest challenge with winning form in last weekend's national triathlon series race in Napier.
But for Doe to win he must put daylight between himself and Brown heading on to the run. Bell will look to do the same, aware of Brown's blistering run.
"If I'm first off the bike or at least within sight of them, I have to feel confident," said Brown. "I can run a lot faster than I did last year."
On that occasion he ran Bell down but did not take the lead until 38.5km into the 42.1km leg.
But Brown is not too concerned about how much he wins by.
"A few minutes or a few seconds, does not matter. I just have to swim as well as I can and keep as close as I can to guys like Luke, Kieran and Pete Jacobs."
Brown reckons he is capable of running close to, or perhaps under, his 2h 44m marathon best. In almost any race, that would be a winner.
"I'm definitely in the shape I was in when I set the record in 2005," said Brown. "I have been swimming well and will go into it at 67kg-68kg - probably the lightest I have been. That doesn't worry me and is certainly a help on the run."
Lawn too has been preparing intensely for the often race-deciding run.
"I have been focusing more on running in the Waitakeres which has already paid dividends," said Lawn. "In the half-ironman in Tauranga I ran a personal best by six minutes.
"Here, I would love to go under my best marathon time [3h 09m]. I have a time in mind. Maybe I can go under 3h 05m. Anything like that should be good enough to win."
Australian Kate Bevilaqua, who beat Lawn in Tauranga, will be looking for a decent break off the bike if she is to hold off Lawn.
In finishing fourth in Hawaii 2007, Lawn ran 3h 10m, Bevilaqua 3h 17m in finishing 24th.
Asked whether she was getting bored with Ironman, Lawn said: "Not by any means. You start with a clean slate every time and do the best you can. I would like to have a lead of between five and 15 minutes going into the run. That would put me in a position of controlling the race. I certainly don't mind being chased."
And, for those wannabe winners, Lawn has a word of warning.
"I'm in a lot better shape than I was in Hawaii where I was carrying a hamstring injury. I'm clear of that. I'm ready to race."
And, for those who are looking for Lawn to abdicate, they might have to wait a while yet.
"I would love to have a baby - but we are thinking in about three or four years."