One of the most eagerly-anticipated races in the history of the Olympic Games is due to take place this evening.

All being well, the Jamaican duo of Usain Bolt and Yohan Blake will progress through their 100m semi-finals at around 7.45pm, thus filling two of the slots in the 9.57pm final.

The charismatic Bolt will head into the showpiece event as the world record holder and the defending champion from Beijing four years ago. As a result, the 25-year-old has been installed as the odds-on favourite to take the gold medal by all of the bookmakers.

However, there is now a new kid on the block and he isn't half fast! Blake currently holds the quickest time of the year - a swift 9.75 seconds. That arrived during the Jamaican qualifiers for the Games, where he left Bolt trailing in his wake. It is also the second time this year that Blake has got the better of his compatriot.

But Bolt is the man for the big occasion, right? There is no doubt he was. Those that witnessed his run in Beijing and then at the World Championships in Berlin just a year later were left open-mouthed.

Then came the next Worlds in Daegu in 2011 and that false start that saw the great man disqualified in the final. Who was on hand to take full advantage and win the top gong? You got it, Mr Blake, who became the youngest sprinter to be crowned champion of the world.

There are those who believe that Bolt has never fully recovered mentally from that night in South Korea. Those in the know feel that his starts to a race are nervous and laboured to ensure that he doesn't go before the gun again.

Further evidence of that came from the horse's mouth yesterday afternoon. Having won his heat inside London's Olympic stadium, Bolt confessed that he stumbled out of the blocks - not for the first time this year either.

The truth of the matter is that 22-year-old Blake is now too good to give a head start to. If he is given a metre or two, he has the ability to take it, leaving his training partner Bolt and the rest of the field staring at his heels in the process.

On the flip side, if Bolt can rid himself of any demons and accelerate out, there will be very little anyone can do to stop him from winning back-to-back gold medals.

Of course the American trio of Tyson Gay, Justin Gatlin and Ryan Bailey - not forgetting Bolt and Blake's fellow countryman Asafa Powell - may have something to say about all of this. All four were extremely impressive during qualifying and they are not just there to make up the numbers.

Yet, you can't help but feel that the winner will come from the Caribbean island, who can boast that they have the two fastest men on the planet so far in 2012.

Sports Mole says: Blake to claim gold! Bolt settling for silver and Gay taking the bronze.