However, as he moved into his early teens the success "dropped away" as he struggled to compete physically with many of his rivals.
Yet he was never disheartened and he was always confident better times were around the corner.
"My coach at the time was Roy Williams (1966 Commonwealth Games decathlon gold medallist) and he always said I was a later developer and to stick at it," adds Aaron. "I always knew if I grew I had a lot more potential."
He was right. Aged 15 he shot up in height and as a good all-round athlete he wisely moved into multievents making his octathlon debut at the New Zealand Under-18 Combined Events Championships.
He finished second with 5044pts, which was good enough to earn him selection for the Oceania Under-18 Championships in Tahiti, where he went on to strike gold with a total tally of 5231pts. Inspired he quit football and so began a whole new sporting chapter.
With no experience of pole vault (which is part of the decathlon but not octathlon) he wisely join the training group of Jeremy McColl - the coach with the Midas touch and the man behind the success of Olympic bronze medallist Eliza McCartney. Yet the challenge of the new event proved demanding.
"I normally pick up most events reasonably quickly, but the pole vault took a lot longer," he says. "It was very frustrating. Even today I have training sessions where I feel I jump pretty well but then when I go into a competition that goes out of the window. I am very right-sided but I had to learn to jump off my left leg. It is a very complex event."
Yet under McColl's coaching - at that point for all events - he achieved his ambition of winning his maiden national title -taking out the 2014 New Zealand junior decathlon crown with 6287pts to further underline his potential.
In 2015 the Henderson-based athlete - even though was still a U20 athlete at the time -performed with pride to score 6983pts for senior silver in the decathlon at the New Zealand Championships. This qualified him for the World University Games later in the year, but, unfortunately, as the season progressed injuries took their toll.
Patellar tendinitis started to hamper him in both knees, although despite no-heighting in the high jump he still picked up a decathlon silver medal at the 2015 Oceania Championships.
Later that year and increasingly compromised by injury he placed a distant 13th at the World University Games in Gwangju, Korea with 6905pts - more than a 1000pts behind the gold medallist Thomas van der Plaetsen of Belgium.
"I didn't go in expecting too much," he recalls of the memory. "I was no way near 100 per cent fit because my knees were completely wrecked. I was the youngster in the field (aged 18) and it was a pretty big competition. I didn't feel I belonged, but it gave me some vital experience. I definitely think had I not gone to World Unis (in 2015), I definitely wouldn't have medalled in 2017."
Post-Gwangju he desperately sought treatment for his knees and experienced a three-month isometric loading programme. This failed to work and in early 2016 he was given plasma injections in both knees yet it was around this time it was Aaron's good fortune he hooked up with a new coach, Matt Dallow.
Matt and his partner the physio, Chelsea Lane (formerly of HPSNZ) described the Kiwi decathlete as having "the worst posture they'd ever seen."
Matt said to me, 'If you don't fix this, you are going to break', explains Aaron
"This is when the whole restructure of my body happened. He stripped everything back and he basically retaught me how to walk. We worked on glute strength because up until this point I couldn't activate my glutes, which is why I kept getting knee pain. We completely changed my technique for each event."
In 2016 as he focused on fixing his body and competed just once, placing a distant seventh at the Australian Championships. Yet over time the body has healed and Aaron pays a huge debt of gratitude to Matt.
"His attention to detail and his ability to look at the movement of the human body and figure out why it is moving like that, is second to none," adds Aaron.
With McColl retained as his pole vault coach January's Queensland Championships revealed his rising promise as he triumphed with a new PB of 7138pts - albeit hampered by an osteitis pubis injury. At the end of March, he placed a noteworthy third at the Australian Championships with a cumulative total of 7246pts
Since late March his injury issues have finally cleared and in the countdown to the World University Games the 20-year-old has managed to put together the best period of training in his career. His preparation has been slightly complicated following Dallow's move to live in San Francisco in December last year, but in regular contact with his coach and with the support of McColl and his training group for pole vault and James Mortimer's sprint group -in Auckland the multieventer has made it work.
Ranked 16th out of the 19 decathlon competitors hardly marked the Kiwi out as medal potential in Taipei and Aaron himself viewed a medal as a remote possibility.
Yet in crazy hot and humid conditions "the pole vault was in 35c which felt like over 40c in the humidity" Aaron remained composed when many around him struggled to cope.
"Many of the guys were complaining how hard they were finding it and that gave me a little bit of hope because I was not feeling too bad," he explains.
At the end of a spectacular first day, the Kiwi sat in provisional silver after smashing his PBs in the shot with 13.59m, equalling his lifetime best in the long jump 7.17m and hacking 1.09secs from his 400m best with 49.75 - after setting out with a far more aggressive approach to the latter event.
Making his way to the stadium the next day he dreamt of winning a medal for the first time. Despite a 4.20m pole vault PB in event eight he had slipped to fifth overall and after a disappointing javelin of 55.23 - more than 7m off his best - he thought his medal chance had vanished.
Yet he was surprised to discover after event nine he had advanced to fourth and should he better the performance of the Belarus athlete Maksim Andraloits in the 1500m by 17 seconds he could yet grab bronze.
As Aaron had a PB of 4:36 and Andraloits 4:43 this looked unlikely, but the Kiwi - in the best shape of his life - targeted a time of 4:25 in pursuit of a medal.
At 800m he was eight seconds clear and then at 1200m he had eked out a 12-second advantage on Andraloits. "I started to build for the last 300m and Craig Motley (the team manager) yelled out 'he's gone, he's gone' (in reference to the Belarussian).
Aaron crossed the line in a new PB of 4:32.11 and after the clock ticked past 4:49 with still no sign of the Belarussian, Aaron could celebrate a most welcome bronze with a otal of 7523 points. Andraloits eventually stopping the clock in a pedestrian 4:59.34.
"It was unreal," says the construction management student at Massey University "Even talking about it today makes me feel pretty emotional."
Naturally brimming with confidence after such a performance he can look forward to the future with optimism. His immediate goal is to snag at least a Commonwealth Games B qualification mark of 7700pts and the Aucklander is hopeful he can improve further.
"The pole vault and hurdles are my weakest events, but they are big scoring events, which gives me lots of scope for improvement."
In the longer term, Aaron hopes to have a third crack at World University Games in 2019 with the 2020 Tokyo Olympics and Simon Poelman's 30-year-old national decathlon record of 8366pts in his sights.
Yet above all else, the rising all-rounder just loves putting his body on the line and competing across two days of exhilarating action.
"The decathlon has everything," he says. "You are almost living with your competitors for two days straight. You make great friends and you genuinely want your mates to do well. I'm not sure it is the same for individual events. It is nice to see the rewards because of the amount of work you put into it. I guess, you have to be a bit crazy to do it."
