While Usain Bolt is going to take some beating, I am expecting a strong challenge from the United States on Sunday night. I think Justin Gatlin is running well enough to win a medal, but I think Tyson Gay is going to be the one to watch. The start is what will preoccupy the sprinters before their race. They might be staring down the track to the finish line but inside they are visualising the first few moments of the race. It will be interesting to see how the different contenders get mentally ready. Some use their emotions to get themselves ready, others are more clinical. Some guys are straight up gladiators while others are very creative. It depends on individual temperament. More than any other athlete, when sprinters get behind the blocks they are going through the technical aspects of the race: they are thinking about their reaction time, their first two or three steps, their body position in that initial transition out of the blocks, when to become fully upright, their stride length and repetition rate and how to maximise knee lift. There will be seven or eight things swirling through their head. It can come down to who is best prepared. Getting a good start is not just down to instinct, it is down to a lot of hard work. At the 1976 Olympics for the 400m hurdles I managed to get my reaction time down to what the 100m sprinters were doing, down to about 0.15sec. That comes with training. The hard thing is to stay focused. If you go on a six-mile run you can let your mind wander but as a sprinter you have to be on top of your game the whole time. A start drill lasts between a second and a half and three seconds – these guys go a long way in three seconds. You have to get focused before every one, doing start after start. It is all about the intensity. Everything about a sprinter’s training is compressed. You have to make sure everything is completely covered because you do not get the chance to make up for an error. Every situation in which you make the slightest mistake is magnified in a race. It goes in an instant. That is the only other way Gay, Yohan Blake or Asafa Powell can hope to beat Bolt – if he makes a mistake. He is facing a different kind of challenge than he did in Beijing; this is a very different race. In Beijing he had his magic moment when everything went perfectly for him. He had no real expectation, everything was new to him. This time it is different. There is much more expectation, much more pressure. It is not just from the supporters but from his sponsors too. These things build up. It was very different for me going into the 1984 Games as the defending champion, and even more so in 1988 – I felt the pressure of expectation. Bolt must find a way of dealing with it. Different factors can affect you in different ways. I struggled to deal with the change of scheduling that reduced the lack of recovery time between races in Seoul in 1988. Bolt needs to manage any challenges he is presented with better than his rivals. Something like the weather can be a big factor: who will cope better if it is cold and wet? Or if there is a strong head wind? I would discount some of the speculation about Bolt’s fitness. People used to tell me I had run with an injury in a race when it had not been the case. I was hardly ever injured but it does get people talking. Such is Bolt’s popularity that he will be surrounded by swirling rumours from everywhere. My take is that if he really was injured we would have heard more about it. I certainly did not advertise it when I was hurt but somebody always talks. So if he was injured we would have more concrete information, I think. The one guy who has more information about Bolt than any other is Blake. As his training partner he will know exactly what kind of condition he is in, how quickly he is getting away from the blocks. He can use that knowledge to his advantage. Blake beat Bolt at the Jamaican trials and that will give him self-belief. But he is not the only one who can challenge Bolt. It might take the race of his life but Gay is in with a chance.