Usain Bolt may have earned greater global fame for his exploits over 100m, but for many athletics purists his record over the 200m is even more impressive.
Since September 2007 the Jamaican sprinting icon has suffered only one defeat over the half-lap distance - when beaten by countryman Yohan Blake at the 2012 Jamaican Olympic Trials – but he has otherwise proved invincible winning two Olympic and four IAAF world titles, not to mention setting the current world record time of 19.19.
Bolt has proved time and time again “the man” over a distance he regards as his speciality but due in a part to a hamstring tear he has raced just once over 200m – running a steady (for him) 19.89 to win, of course, at the IAAF Diamond League fixture in London.
Leading the challengers is Justin Gatlin, who raced to victory in a rapid 19.75 in his one and only competitive outing over 200m this year at the US Olympic Trials.
At last year’s world championships, Bolt outgunned Gatlin to strike gold by a margin of 0.19 but the 34-year-old American, who was world 200m champion 11 years ago, will be desperate to reverse those finishing positions in Rio.
200m/400m double ambitions for Merritt
Gatlin is, surprisingly, joined on the US 200m team by 2008 Olympic 400m champion and 400m world leader LaShawn Merritt. The 30-year-old one-lap specialist has also excelled this year over 200m running a stunning PB of 19.78 in Nassau before chipping 0.04 from that time in the semi-finals of the US Trials to clock a world leading time before sprinting to 19.79 for second in the final.
His 200m quality this year clearly elevates him to podium contender, however, his main priority will be to regain his 400m crown earlier in the programme and it is not yet known how his exertions in his number one event will impact on his 200m.
Rounding out the US squad is Ameer Webb, another threat. After a couple of seasons in the doldrums, the former NCAA 200m champion considered quitting, but this year the Californian has enjoyed a resurgence winning Diamond League races in Rome and Doha and blasting to a new lifetime best of 19.85.
Miguel Francis, training partner to Usain Bolt, could be another to watch in Rio. The 21-year-old from Antigua and Barbuda was a 2015 world championship semi-finalist but this year has powered to a national record 19.88 to emerge as a genuine threat.
The 2009 world championship silver medallist Alonso Edward has been one of the most consistent 200m athletes on the Diamond League circuit and the Panamanian is another likely contender.
Jamaican champion Yohan Blake - the 2012 Olympic silver medallist and second fastest 200m man in history - also competes. The 26-year has been bedevilled by injury for several seasons but posted a solid 20.29 to land the Jamaican title and could be a factor.
Other Jamaicans selected are three-time world championships finalist Nickel Ashmeade and 2015 world championships semi-finalist Julian Forte.
Canada boast a powerful-looking three-man team led by national champion Brendon Rodney who made a big breakthrough to run 19.96 this season. Joining him on the Canadian team are Aaron Brown (20.00) and Pan American champion Andre De Grasse (20.16).
Other entries include two-time Olympic finalist Churandy Martina of the Netherlands, British duo Adam Gemili, the 2014 European champion, and Nethaneel Mitchell-Blake (19.96) and Christophe Lemaitre of France, the 2011 world bronze medallist. The 2015 World bronze medallist Anaso Jobadwana of South Africa is selected, although he has yet to compete this year because of a pelvic injury.
Steve Landells for the IAAF