It should have been a special day for Harrison, the morning of his Wallabies debut. However, the Brumbies lock woke up in Sydney to find himself at the centre of an unwanted media storm.
Some ill-advised and ill-timed comments in a column by British and Irish Lions back Austin Healey saw Harrison described as "an ape", "the plod" and "a plank".
Healey had clashed with Harrison during the tour match against the Brumbies - however the comments in The Guardian had still come out of the blue.
Harrison, though, made Healey - whose tour had ended prematurely with a back injury - eat those words as he wrote himself into rugby folklore.
With the Lions trailing 29-23 with two minutes left, the tourists had a lineout 10m from the Wallabies line. A score was by no means a certainty, but the Lions pack - spearheaded by skipper Martin Johnson - would have fancied their chances of setting up a rolling maul to rumble towards the line.
Harrison and the Australia pack had other ideas. The so-called 'Plank' snaffled the ball from Keith Wood's throw from in front of Johnson and the chance had gone, with Australia claiming the series 2-1.
But ahead of the return of the Lions Down Under, Harrison has played down his role in the win.
"It is humbling to remembered," Harrison, who now coaches Narbonne in France, told Sky Sports.
"To me I just played such a small part in what happened. I was part of an Australia squad that won 2-1 against the British and Irish Lions for the first time in over a century.
"It was my first Test, too, so my memories surround that. It was a special day for me - and my father as well as he got to see his son play for the Wallabies for the first time.
"My memories are certainly not clouded by what was said, written or ghost written in a publication by Mr Austin Healey. It is not something that I was bothered about.
"I have spoken to him since and we've had a beer, I even let him buy me one. He was obviously a good player but he has his faults like all of us. His main fault then was speaking out before the third Test while he was on his way home with an apparent back injury, while I was preparing to play."
Harrison, who went on to play for Ulster and Bath before returning for a brief stint with the Brumbies, claimed he just ignored the comments at the time.
"To be honest if you need something that is written in a paper as motivation you are in the wrong sport," he said.
"All I was concentrating on was doing my job and making sure I did everything I needed to do as heading into the Test I was a little bit intimidated by the quality of the British and Irish Lions players."
Harrison went on the appear 34 times for Australia in total, including at the 2003 World Cup.
However he still has fond memories of that game-changing lineout against the Lions.
"I have selective memory of that now and I think as I have got older I have allowed myself to play up the importance, so I think I will stay away from the videos of it for now," added Harrison, who will return to Australia for the second and third Tests this summer.
"In truth, though, it was just another small part that happened to go right as we had another lineout to defend before it was all over.
"With lineouts you need a lot of things to work. You need equal parts bravery, luck and naivety. There are also a lot players involved to make sure it goes right.
"The luck element meant Keith Wood under-threw the ball, while I think 'Johnno' was maybe a little bit too relaxed. Then Michael Foley and Rod Moore had to lift me as I couldn't jump out of bed and the timing was just right. It was all these little things that went right.
"I am just pleased to have played my part in the win. I was delighted to still be on at that stage in my first Test. To get past half-time and not get hooked was brilliant."
The pinnacle of British and Irish rugby, the Lions tour, returns and heads to Australia. Sky Sports will broadcast the entire tour live with all three Tests against the Wallabies plus all seven tour matches. For the first time, the inaugural tour match will take place in Hong Kong. The British & Irish Lions tour will be the fifth consecutive tour shown exclusively live on Sky.