When I was a kid I used to wait excitedly for the Olympics to start and then spend the first week frustrated because it was all about swimming and I wanted to watch athletics.

Today, a long time after enjoying my first Olympics in Montreal in 1976, I will be going through the same wait.

Back in 1976, I at least had the excitement of watching my countryman David Wilkie win the breaststroke event.

The commentator’s excited shout, “And it’s Wilkie!” as he touched home to take the gold medal remains a classic moment in Scottish broadcasting.

This time around I’ll be looking out for Cesar Cielo, the Brazilian who won gold in the 50 meters freestyle in Beijing and who is favourite to repeat his win.

I interviewed Cielo in April for this Reuters story.

He was pleasant, charming, likeable and generous with his time, in short, an example to most of the world’s football players, who are rarely charming, rarely likeable, rarely pleasant, and rarely generous with their time.

But I’ll be torn. Cielo was caught taking a banned substance last year and was inexplicably let off by Brazilian swimming association. (I explain more about the case here.)

I have a pretty radical take on doping. I think that anyone caught taking a banned substance should be banned for life unless they can prove convincingly there was a mistake. It’s the best way to stop cheats. If they realise their sporting life is over if they get caught, more of them would think twice about cheating.

I asked Cielo about the incident when we met and he looked visibly uncomfortable when I brought it up.

“My life hasn’t changed but I feel like as person I have changed a lot,” he told me. “I feel like I grew up a lot to overcome the situation. I had to learn who my real friends were, who I  could talk to and who wanted to kill me. It opened my eyes to see who was supporting and who stood by me. It challenged myself to see if I could overcome something like that. Today I am much more prepared for any eventuality and any setback.”

Whatever the truth of the case, and there are still questions over what really happened, Cielo has every reason to feel confident about his medal chances.

He owns the world record (20.91 seconds) which he set in 2009 before synthetic bodysuits were banned, and has the fastest time in the world this year (21.38 when I wrote this story).

He will go to London as the favourite and I wish him luck. But as far as I am concerned, there will always be an asterisk alongside his name.