There are just the four weeks to go now before the big clash of the "heavyweights" of the sprint world. The "Burn-Up In Berlin", you might call it: the men's 100 metres final at the track and field World Championships on the evening of Sunday 16 August.
In the yellow vest, standing 6ft 5in, weighing 195lb, all the way from Trelawny, Jamaica, the world record-holder at 100m, the world record-holder at 200m, the Olympic champion at 100m, the Olympic champion at 200m... Usain "Lightning" Bolt.
In the white vest, standing 5ft 11in, weighing 165lb, all the way from Lexington, Kentucky, the fastest man in 2009 at 100m, the fastest man in 2009 at 200m, the reigning world champion at 100m, the reigning world champion at 200m..."Typhoon" Tyson Gay.
As a born and bred Kentuckian, Gay might be expected to qualify for a different sobriquet, but then the lad from Lexington happens to be cut from rather more self-effacing cloth than the celebrated "Louisville Lip".
In the lead-up to the so-called Fight of the Century at Madison Square Garden in 1971, Muhammad Ali said that the undefeated Joe Frazier was "so ugly he should donate his face to the US Bureau of Wildlife".
Looking ahead to the Burn-Up In Berlin, Gay refers to his seemingly unbeatable rival as "a beast," "a freak" and "a monster". But far from giving the Lightning Bolt some boxing-style lip, he is in fact proffering the utmost respect.
"I give respect where respect is due," Gay says, speaking from his European summer base in Munich, ahead of his appearance in the Aviva London Grand Prix at Crystal Palace next week – he runs in the 200m on Saturday, Bolt in the 100m on Friday. "This guy deserves due respect. What he does out on the track is stuff that other people can't do – whether he slows down, whether he runs through the line. And no one has ever run as fast as him.
"So I give respect where respect's due. And that, right there, motivates me as well, to train harder and be the best I can be and reach goals that no one has ever done before."
Sadly for Gay and for the watching world, the American was not the best he could have been at the Beijing Olympics last summer. Far from fit after a hamstring injury had blown a great hole in his pre-Games preparations, he exited the 100m at the semi-final stage.
He could only sit and watch – and wonder – as Bolt took the world record down to 9.69sec in the final, while applying the brakes and celebrating some 25 metres out from the line. Then he had to do it all over again as Bolt blitzed to the 200m gold in 19.30sec, breaking Michael Johnson's supposedly untouchable world record for that distance.
The International Herald Tribune ran a cartoon of Bolt lazing in an armchair beyond the finish line, with his gold spikes off and his feet up, enquiring of his still toiling rivals: "Where have you been?" It promises to be different in Berlin, thanks to Gay.
His response to the Beijing Lightning Bolt show has been to come out fighting in 2009, in better shape than he was in 2007 when he completed the sprint double at the World Championships in Osaka, winning the 200m ahead of a Bolt who was starting to show signs of realising the potential he showed as a teenage prodigy.
At the Reebok Grand Prix at Randall's Island in New York at the end of May, Gay clocked a stunning 19.58sec for 200m – a time only Bolt (19.30sec) and Johnson (19.32sec) have bettered for the distance. At the Golden League meeting in Rome nine days ago he ran 9.77sec for 100m, equalling his own American record.
Four weeks out from the World Championships, it is Gay who stands on top of the global rankings. Bolt's best times thus far in this post-Olympic season are 9.79sec for 100m, which he clocked in the rain in Paris on Friday night, and 19.59sec for 200m. Not that Gay considers himself to be the fastest man in the world now.
"I believe he is," the 26-year-old says of Bolt, somewhat earnestly, speaking with a soft, southern drawl which underlines his engagingly understated manner. "These times that I'm running right now, they don't mean much to me – until I'm peaked up and ready to run my fastest time and show what I'm capable of doing. Right now, I still believe he's the fastest man in the world."
The fact is, in getting to grips with his Project Bolt (in a more convincing fashion than Dwain Chambers has managed to do in his declared mission), Gay has been obliged to focus his sights some way beyond 9.77sec and 19.58sec. Recalling his reaction to Bolt's awesome 100m run in Beijing, he says: "I didn't really realise what he had done until they showed the replay and that was so exciting. I kind of thought: 'The bar has been raised to 9.69sec. I know what I have to do. I have to train my mind and my body to go where no man has gone before'.
"I kind of knew then that I had to train my mind to run what Usain Bolt was running and to try and run faster than he was running, because you can't programme your mind to run anything less than that. If he hadn't done what he's done, I wouldn't be thinking about running 9.6sec."
All of which rather suggests that the human speed barrier could be broken again when Typhoon Tyson and the Lightning Bolt finally get it on in Berlin. It was shattered the last time they met on the track. That was in the 100m at the Randall's Island event 14 months ago. Bolt, running in only his second serious race at the distance, clocked a world record 9.74sec. Gay was a somewhat stunned runner-up in 9.85sec.
"It's a possibility," the American says now, on the subject of beating the clock in Berlin, "because I'm pretty sure that he's going to go out there to try to break two world records. He's going out there to run as fast as he can to win and that's what I'm going to do. If running as hard as I can is a world record, I'm going to be the happiest man on earth."
So how hard might the happiest man on earth have to run in order to be the fastest? Sub 9.50sec even? "I don't know about that," Gay says, "but with Usain Bolt you never know what's in store. If he runs something like 9.4sec, my mind's not even there yet. But I do truly believe that the world record could be broken, so maybe even 9.5sec, because he believes that he can run that fast. And that's where it starts first and foremost: belief."
Gay should know that. Back in 2007, when his coach Lance Brauman was serving a 12-month sentence in the Texarkana Federal Correctional Institution for the fraudulent payment of athletes from student assistance programme funds, he managed to maintain his self-belief and show the rest of the world – Bolt included – a clean pair of heels in Osaka. Two years on, his best hope of beating Bolt in Berlin might be to get out of the starting blocks ahead of the Jamaican and put the pressure on.
"I'm not sure," Gay says. "This guy seems pretty fearless. He's having fun and he's fearless, and that's a dangerous competitor. It's normally natural for someone to tighten up a little bit but this guy's such a beast. I'm not very sure what he's going to do.
"I've studied some film of him running but not a lot, because he's what you'd call a monster. In some sports in the United States, in football and basketball, you call certain people freaks. That means that they're tall and they're able to do some things that nobody's ever heard of. He's in a class of his own, like a LeBron James or a David Beckham."
For those unfamiliar with US sports, James is a 6ft 8in basketball player with the Cleveland Cavaliers who goes by the title "King James". Beckham is a 6ft 0in footballer with Los Angeles Galaxy, of whom George Best said: "He cannot kick with his left foot. He cannot head a ball. He cannot tackle, and he doesn't score many goals. Apart from that, he's all right."
The Beckham analogy might not be the best, as it were – a little lost in trans-Atlantic translation – but you get Gay's drift. "It's kind of hard to study someone so great because he does things differently to other people," he continues, with Bolt in mind. "Also, his mind frame is different. His mind frame is on the 9.5sec level. A lot of people don't think like that. That makes it even tougher. Just mentally keeping it on your mind, to me, that's the key."
The key to unlocking the Bolt in Berlin, perhaps? Only time will tell. Something less than 9.69sec of time, in all probability.
The Aviva London Grand Prix takes place at Crystal Palace on 24-25 July. Tickets available at www.uka.org.uk or telephone 08000 5506056
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