Double dose of Bolt vs Gatlin will showcase greatest rivalry in sprinting
After avoiding each other for what seemed like an eternity, the titans now must clash.
Usain Bolt, the laid-back Jamaican who just happens to be the fastest man ever clocked, against Justin Gatlin, the super-intense American who has blown away every foe he's faced in this track season.
Like a pair of gunslingers, they will battle over 100 and 200 meters at the Bird's Nest during these world championships.
Some sprinters - primarily Tyson Gay of the US and Bolt's compatriot, Asafa Powell - no doubt feel they have a shot at gold in those elite events, but the finals should be races of two.
Gatlin, who has been banned twice for doping and now is tested more than a mother's patience, has recorded this season's four fastest times in the 100 and the two quickest 200s.
Bolt, struggling with niggling injuries, has had a quiet 2015 but clocked two 9.87s in London last month to show he is warming to the task of defending his crowns here - the scene of his Olympic heroics in 2008.
On current form, Gatlin is the tip with runs of 9.74, two 9,75s and a 9.78 tucked under his belt this year in the blink-of-an-eye 100, and 19.57 and 19.68 in the half-lap race.
However Bolt, who owns the sprint records (9.58 and 19.19) and seems like the only person on the planet capable of breaking those ridiculous marks any time soon, can never be underestimated - especially in terms of heart and pride.
While the men's dashes look like a two-horse race, the women's sprint field is wide open.
Jamaica's 'Pocket Rocket', Shelly-Ann Fraser-Pryce, is as quick as her name is long. The Olympic champion should defend her 100m title, but she can expect strong challenges from compatriot Elaine Thompson, impressive Americans English Gardner and Tori Bowie, Nigeria's Blessing Okagbare and Cote d'Ivoire's Murielle Ahoure.
The 200 is up for grabs and the US-Jamaica hegemony could be broken by the Netherlands' Dafne Schippers due to the voluntary absences of Fraser-Pryce and the woman who would have been a prohibitive favorite, Allyson Felix of the US.
The greatest threats will come from Candyce McGrone of the US and Jamaica's Thompson in what could be a blanket finish.
The sprint relays, per usual, are a toss-up, with the Americans showing a great ability to drop the baton at major meets.
If they carry the stick all the way around the track, the US should hold off defending champ Jamaica in the men's event, and Asia could see a podium finish through a smooth Japan foursome. Britain and Antigua and Barbuda will also be waiting to pounce on any mishaps.
Again, provided there are no mishandlings, Jamaica's phenomenal sprint depth should see it cross the line ahead of the US, while bronze looks like a European battle between Ukraine, the Netherlands and Britain.
On the women's world relay stage, the Bahamas is a perennial contender, with fellow Caribbean country Trinidad and Tobago also a consistent threat.
All of those scenarios are way down the world championships track, however. The pace of the meet will be set on Sunday night when Bolt and Gatlin shoot out of the blocks in the 100m final.
There is little love between the US and Jamaica sprint teams and the winner, be it the guy in red, white and blue or the one wearing green and gold, could set the tone for the rest of the week.
The US will cheer on the man in the proverbial black hat, Gatlin, while most of the rest of the world will be behind the guy wearing the white one.
