Valerie Adams knew weeks before she went to London in 2012 to defend her Olympic shot put title that she would be facing a drugs cheat.
In Switzerland her coach, Jean-Pierre Egger, had seen how her main rival Nadzeya Ostapchuk had vanished from the summer Diamond League circuit in Europe. Since the northern spring she had only competed in her home nation of Belarus, a country part of the Soviet Union until 1990, that was notorious in European track and field circles for illegal drug use.
Egger said to Adams, "You will see that she will not start in Europe, she will not go outside her frontiers, to not do doping control. She will come to the Games charged with drugs. You will have to throw twenty one and a half (metres) if you are to win against a doped athlete."
During the previous 12 months, Valerie and I had worked on her biography, to be published after the London Games.
In the course of the intensive interviews you need for a 75,000-word book, you get to know someone in a relatively limited time frame as well as you do many of your closest friends. With Valerie, the process was a delight.
She was intelligent, kind-hearted, and sometimes laugh out loud funny. It was a small step for my wife and me to go from liking her to loving her.
There are many people important in Valerie's sporting life, and for the last decade Egger, a huge bear of a man - himself a former world-class shot putter - has been a huge part of her success.
He'd spotted her when she was a 16-year-old novice. He was in New Zealand as a conditioning expert with the successful Alinghi challenge for the America's Cup. A session was held with a group of young throwers, and Egger said to Valerie's original coach, Kirsten Hellier, that in the shy kid from South Auckland "you have gold".
When Hellier moved to coach in China, Valerie approached Egger. He said he would like to help, but she would need to move to Switzerland.
He was a warm, welcoming rock, but visiting her in June 2012 at the Swiss Olympic training centre where she was living was a shock.
Walking down the corridor to the room she rented, the institutionalised feel was of a Spartan boarding school, with a hint of a minimum-security prison.
Her room had no cheery signs on the door. The Swiss are famously efficient because they have rules they apply rigidly. Attaching photos and posters to the wall was forbidden.
There was a single bed, a tiny fridge, a kettle, nowhere to cook, and a shelf that ran along the end of the bed. The computer that provided a Skype lifeline to her family in Auckland was perched on the shelf. There wasn't enough room for a desk and chair.
One of the handful of drawers under the shelf was her New Zealand treat drawer, filled with lollies and mementoes that family and friends had posted to her.
No wonder she'd later say there were nights when she found she was crying herself to sleep. My admiration for her courage and determination went to even higher levels.
So six weeks after seeing Valerie in Switzerland, it was hugely frustrating to see Ostapchuk throwing further than her in London. Jean Pierre's words about drugs echoed in the mind, but as dubious as Ostapchuk's form was, there was no concrete evidence.
How fantastic, six days after the shot final in London, to have the phone ring at our home in Stillwater, north of Auckland, in the early hours of the morning. I'm a much deeper sleeper than my wife is, so I was awoken not by the phone, but by excited screaming which, if I'm being completely honest, is rarely heard in our bedroom.
Gradually, as the mist of sleep cleared, it was obvious it was Valerie on the line, yelling with joy.
She was calling from the side of the road on the way to Jean Pierre's house in Neuveville, to pick up a new pair of throwing shoes. Everything changed when she answered a call from Dave Currie, the Kiwi team manager in London, to say Ostapchuk had failed a drug test, and been disqualified. Valerie had won gold.
In real life, not every villain is caught. Not every good person gets the reward they deserve. But in a lifetime of being lucky enough to make a living following a passion for sport, I can't think of any occasion when justice has been better served in sport than when the scientist in the 2012 anti-doping lab at Harlow, not far out of London on the way to Cambridge, checked the results of Ostapchuk's A and B samples and confirmed all of Egger's suspicions.