Throughout my playing career I've heard many times that you'll know when it's time to call it a day. They said: "One morning you will just wake up and know instantaneously that you want to retire or it's time for a change of direction."
Well, I'm here to tell you it has never been that black and white to me.
Over the years there have been moments of self doubt, confusion and questions that haven't always had a straightforward answer, but whenever these challenging times have cropped up, they have always been extinguished as quickly as they have arisen. It has invariably come back to the enjoyment and desire factors.
Motivation must come from within and as soon as that inner flame is doused, the will to succeed and carry on has only one conclusion. For me it may be as simple as reading an inspirational story, hearing a favourite song, watching some cricket highlights or just having a game of backyard cricket with my son Austin, to get the juices flowing.
Cricket is in my blood, I love the one-on-one battle, the competition, the confrontation, the duel, the camaraderie of achieving goals together and the fact that you never know what is around the corner. The thought of being able to achieve something new everyday, to believe you can improve and to test yourself, have always drawn me to the challenges that lie ahead.
It has been both bewildering and expected from my perspective. The former, because I've always seen myself as just a cricketer from the western suburbs of Sydney who happened to be lucky enough to live out his dreams and play for, and captain, Australia. To have so much attention on my departure just feels strange, but I can also understand that after having played for Australia since Boxing Day 1985 I have been a part of people's lives for nearly 20 years. Many have shared my ups and downs, they have seen my career develop and have been tremendously supportive, and, as such, feel as if they have played a significant role in my career, which they have.
Cricket is big news and high profile, which brings both rewards and drawbacks, but without doubt, the positives outweigh the negatives. When you get to a certain age as a professional cricketer, you tend to be categorised.
As a bowler, 33 - 35 is an age when the issues tend to focus on how much longer have you got rather than what's happening now. A batsman may have the luxury of a couple of extra years' grace, but it will and does come.
Again, I can comprehend this line of questioning, but I will always argue that age is irrelevant unless you have two competing players of equal skill, desire, commitment and fitness levels. This criteria equally applies to youth and if someone meets these requirements at 15 years of age, then their youth shouldn't be used against them.
My decision to retire was made in consultation with my family and my management. It's been a decision that has evolved over a period of time and one I believe has been made at the right time.
I'm glad that I didn't finish after last season's Sydney Test, even though it would have been a fairytale finish. I knew I had something left inside. Deep down I felt I could still improve and I didn't want to finish while not playing consistently well.
As a team we still have important goals to achieve, like winning in the Windies and historically taking on Bangladesh and Zimbabwe for the first time in Australia.
Many will say, "But what about the Last Frontier - winning away in India?" In a perfect world it would have been nice to have a 'crack' at it, but it will now be a challenge for Ricky Ponting and the boys to take on. If Australia do go on to win in India, I'll feel comfortable in the knowledge that I have played a small part in that process.
Ricky has already shown he has the qualities to be successful and clearly has the respect of his peers, and, crucially, seems to enjoy the added responsibility that the captaincy requires. His role, like all captains before, is to develop players and get the best out of them. To pass on traditions, create your own and enhance the culture and values of the team are important, and a challenge that must be embraced. It is an honoured position, which can be enormously satisfying, sometimes frustrating, but always stimulating, and one that must never be taken for granted.
Playing for Australia has always been a huge honour - knowing you are representing 20 million people, and living out the dreams of many. It hasn't always been smooth sailing; in fact, Test cricket was a struggle for the first couple of years. I have to be thankful for the patience and belief of the selectors of the time.
My first emotion upon hearing my selection was panic - am I good enough? Will I be scared and intimidated by the press and notoriety? Can I really be successful?
These were just a few of the thoughts and doubts clouding my mind. I was also excited and thrilled at the same time, but in reality I was hoping rather than expecting to do well.
My big breakthrough came after 26 Tests when everything just came together at Leeds for my first Test century. It's a moment a cricketer never forgets. For me the first thing I recall is how dry my mouth was when I reached 99. I couldn't summon enough saliva to chew my gum; my heart began to thump so hard I could feel it through my sweater and my palms sweated up so quickly that my grip on the bat was threatening to become unstable.
When I pushed that single through the covers, it was just the greatest sensation, an overwhelming surge of satisfaction, contentment, tranquility and excitement all rolled into one.
It was also a massive relief because I'd always wanted to score a hundred and expected to do so; but until you actually do it, those doubts can linger and eat away at your self confidence.
Claiming the World Cup as rank outsiders in 1987 on the subcontinent was the catalyst for the winning era we are accustomed to now. Defeating England 4-0 on the '89 Ashes Tour was a coming of age for the likes of [Mark] Taylor, [Dean] Jones, [Merv] Hughes, [Ian] Healy and myself and remains my favourite tour in terms of enjoyment and achieving results against the odds.
Akin to climbing Everest was beating the Windies on their home turf - a feat we achieved in 1995. Unbeaten for 15 years worldwide and 22 years by Australia, the win in Jamaica was probably my most satisfying from a team point of view. At least that was my excuse for waking up in the whites, half spike batting shoes and baggy green the next morning.
A double century and a huge partnership with twin brother Mark was my greatest triumph in terms of batmanship, because it was against the best attack, in the most critical Test, under the most trying conditions. This was when all the sacrifices, training and aspirations came together and made everything worthwhile.
Coming from a seemingly impossible situation in the 1999 World Cup was also a memorable time and one to cherish because it was executed under intense scrutiny and pressure. It was a great example of a team coming together and really wanting to turn things around.
When you come through adversity it seems to magnify the sense of accomplishment and heighten the celebrations.
Of course, there have been many down times during the journey that have influenced my character and help shape the vision I have and the values needed to survive and succeed. I can still recall sitting in the Eden Park change rooms as a 20-year-old, after scoring 0 and 1, being verbally assaulted by John Bracewell [the Kiwi off-spinner] during a match we lost comprehensively.
It was a series loss, topped off by being bowled out for 102 in the second innings. The dressing room was like a morgue, heads were bowed, the occasional whispered work broke the eerie silence; some uncomfortable glances at each other were exchanged, and the scent of a heavy defeat hung in the air.
My thoughts drifted off to a place I didn't want to visit. I wondered if I'd ever play in a winning Test team, was I good enough to make the grade and could this team turn things around. It didn't seem like it at the time but it was a moment that has helped me stay grounded during the victorious times, and one that I'm glad I experienced.
My first tour of Pakistan was an examination of the toughest kind. A string of questionable decisions, poor form and a culture shock had me in a fragile state of mind, which culminated in a bizarre dismissal during the second Test.
Just when I thought I was making some headway with a determined 20, all I had to do was survive an over of off-spin from a part time bowler before the Test concluded to get some confidence back.
On what turned out to be the final delivery of the match I busted back an innocuous 'half tracker' to the bowler.
Looking back, this was no doubt the lowest point in terms of confidence and self-belief during my career, and one where I contemplated my future.
Of course, there have been other periods of difficulty, but with each, the challenge always remains the same. There is only one way to overcome it, and quite simply, it is hard work and discipline.
I believe in many ways you can judge a player's worth to the side by how they overcome adversity. Attitude will always be the companion to this trait and without it there will be no longevity in the sport. Many of these lessons have been put to use over the past 12 months when the jury was out on my form and position in the side. I certainly checked out a lot of the views that were written on me, some of which were perfectly reasonable, others debatable and some totally outrageous. All of which in the overall context didn't matter because I knew there was still a fire in the belly and the skill level was also there.
If I could trust myself, work hard and keep it simple, I knew I could turn things around.
Throughout my career I have never needed any extra motivation to do well, because quite simply, all I ever aspired to was to make the most of my ability and never give in no matter the situation. If anything was ever needed to really get me going, it was someone writing me off, or telling me that I couldn't do it. Perhaps this is why I performed so well in Sydney, because the stakes were high and the pressure pretty intense, and as such I was on the edge, nervous but focused, just how I like it.
I was amazed at the overwhelming support last year in Sydney, and from around the world, and, without doubt, it inspired me to perform on the day.
Many fans are incredibly loyal, some to the point of being almost obsessive. I've had people name their children after me, a man tattoo my signature into his arm and many others regularly write to me over a 20-year period. I hope I have repaid them for their loyalty and would be happy if they said about me: "That guy always gives his best and loves representing his country."
Life after cricket, I'm sure, will be hectic, because I'm always looking for a new challenge, and it's in my nature to give it everything once I commit to it. Writing an autobiography is something I'm looking forward to, as is keeping my association with various newspapers for whom I write.
Commentary also looms as a possible option, whilst a pilot for an Australian TV show is in the pipeline. Cricket will always be in my blood and an administration role could be an option if I believe I can make a positive difference.
Charity work has been a real life experience so far and I love the associations I have with the kids in India and I look forward to continuing and expanding my role in the years to come. Shortly I will formalise my fundraising activities in India, by setting up a foundation in India, and set about raising funds to build a new school near Kolkata.
In Australia, I'm currently setting up a foundation to help the disadvantaged kids with potential in the sports and arts disciplines.
Speaking of kids, I can't wait to spend time with my three - Rosalie, Austin and Lillian. Watching them grow, develop and experience life has been something I've missed large chunks of in the past and I owe them plenty of quality time.
The same can be said of Lynette, who has been with me since leaving school and my success definitely wouldn't have materialised without her love and guidance. Being a parent is the greatest challenge and responsibility because you can shape the way your kids see and view life, and it's something I'm really looking forward to.
Sydney to me is the perfect place to retire for many reasons. It's one of the best venues in the world; it's been my home ground throughout my career; all my family and friends will be there; I will be playing against India, a team and country for which I have great admiration; my Indian friends will be able to be part of the occasion through the TV coverage; I am very fit and I am very much on top of my game. I've always wanted to finish on my own terms and right now I feel as if I'm in the best form of my career, and I can't think of a better word for anyone to say about me when I finish other than. "Why?"
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