Sir Mo Farah and Usain Bolt are two of the most recognisable figures in athletics.
Bolt propelled the sport to new heights during his remarkable career, finishing his stint with enough gold medals around his neck to open a personal Fort Knox. His playful personality before the starting gun and past the finish line drew in gargantuan viewing figures and no world record was safe when he arrived in peak condition.
His retirement and subsequent adventure into professional football - which came to a quiet end this week - has left a seismic chasm in the sprinting world. There is no shortage of talent filling the void in Bolt's old competitions, but nobody can get close to the Jamaican's appeal or personal bests.
As for Farah, the indefatigable 35-year-old has won the hearts of as many Brits as he has dominated tournaments. Farah holds almost every British record from the 1,500 metres to marathon, underling his remarkable knack of transcending distances and raising the country's athletic standards to new heights.
The Somalia-born runner more than competes with Bolt in the medals department, accomplishing the double-double in the 5,000m and 10,000m at the Olympics in 2012 and 2016 respectively. Silver medals at the World Championship in Daegu and London are the only blots on his infinitely immaculate copybook.
Usain Bolt vs Sir Mo Farah
As you can see, it's no surprise that Farah and Bolt became the poster-boys for athletics during the middle portion of the 2010s. The photograph of them performing each other's trademarks gestures - the lightning bolt and 'Mobot' - at the London Stadium quickly became iconic and solidified their growing celebrity.
So, it should come as no surprise that a few athletics fans decided to float the idea that Farah and Bolt should race one another over a predetermined distance. Although a 10k runner taking on a 100m sprinter might have seemed flawed from the start, Farah's ability to command shorter distances opened up the possibility of finding a middle ground.
The lucrative race became a major topic of discussion shortly after the London games, with Farah even encouraging Bolt to accept his challenge in person. It quickly became established that 600m would be the desirable distance with the sprinter noting: “Six hundred for sure I can try because I’ve done 600 metres in training."
Racing over 600 metres
Both athletes would have raised money for their respective charitable organisations but, unfortunately, the lucrative proposition never transpired. With Bolt now indulging in the luxuries of retirement and Farah shifting his attention to marathon-running, it's highly unlikely that sports fans will ever see the pair in direct competition.
However, that doesn't stop us from wondering exactly how the challenge would pan out and there is certainly a precedent for all-star races in athletics. After the 1996 Olympics, 100m and 200m champions Donovan Bailey and Michael Johnson competed in a special 150m race branded as 'World's fastest man.'
Yet Farah vs Bolt would mean so much more with sprinting and distance running colliding in the most Frankensteinian of match-ups. Assuming that 600m would have been finalised as the distance and that both athletes would be arriving at the event in their primes, we can form a clear opinion about the result.
So, all that considered, what do we actually know about Bolt over a longer distance and Farah over a much shorter mileage?
Bolt actually started his career as a 400m runner, so is well versed in maintaining his remarkable pace over a quarter of a mile and utilising the long stride that made him such an unlikely 100m champion. The Jamaican produced a time of 45.28 seconds in 2007, but could easily have bettered that time if he continued to focus on the longest sprint.
Crunching the numbers
The million dollar question is whether Bolt could sustain his powerful form through the final 200m and it goes without saying that Farah is no mug over 400m. When you consider the Brit clocked a 100m time of just 12.9 seconds in a 2012 BBC Superstars Show, it would be easy to think that Farah would be out of the race in an instant. But you'd be wrong.
During Farah's victory in the 10,000m in 2016, he was able to record a remarkable split of 55.3 seconds through his final lap, overcoming Paul Tanui and Tamirat Tola in the process. But - of course - he has bettered that time on numerous occasions during his foray into the 1,500m in 2013.
It must be assumed that Farah could actually produce a 400m time in the region of 48 seconds, suggesting that the 35-year-old would be tidily beaten over a sprint distance. It makes the final 200m a key area of focus and when both athletes reached the bell, the race would be as much about their physique as it is their time.
Although Bolt has the type of gait that allows him to gobble up the track, his incredibly muscly frame becomes a huge inconvenience as he reaches the aerobic sections of a race. He would have to dial down his 400m time or face crashing around the final bend as lactic acid begins to set in.
Six-hundred metres is uncannily close to the 50:50 boundary of aerobic and anaerobic respiration, although it slightly borders on suiting Farah's energy system more. Runner's World speculated in 2013 that a distance of 565m would actually be perfect, while still disclaiming that Farah runs far closer to 100% aerobic than Bolt does to 0% during their preferred distances.
Deciding the winner
Also in Farah's favour is research from the University of Berlin who offer their own 'perfect race' of 495m based on power law and data from over 1.5 million runners. Further to that, Farah is known to train over distances of 600m on a regular basis whereas Bolt - despite claiming to workout over one-and-a-half laps - spends a lot of time covering explosive, short runs.
Perhaps the balance would tip in the favour of Bolt if he had continued to pursue a career over a longer distance, looking strong down the home straight during his early 400m wins. By the time the charity race had been touted, though, he was focusing on the shorter sprints and his quarter-mile time retreated to 46.37 seconds at the 2015 GC Foster Classic.
The more evidence, the more it seems that Bolt would be biting off more than he can chew at 600m. However, what is far more difficult to predict is the mental side of the race.
Both athletes would need to devise a sound plan for their run and this actually applies a lot more pressure on Farah, who would face having to match the world's fastest man at the gun. It wouldn't be easy for the Brit to start with the kind of pace that could force Bolt into slowing drastically.
Farah would have to settle on a tempo that allows him to keep a consistent distance behind Bolt, before picking the right moment to call upon his trademark kick. Leave it too late and it would become a direct battle between Farah's fresher legs within a jaded technique and Bolt's fatigued stride in a more powerful frame.
Farah gets the nod
Just going over all the variables is enough to get athletics fans salivating and it would have been fascinating to see both athletes take part. If nothing else, it would have been an enthralling experiment for the sport, especially if both competitors were allowed a designated training period.
But, all things considered, Farah would have to be the favourite over 600m. In this wonderful, hypothetical scenario, it would have to be imaged that Bolt would hold the lead after one lap but Farah would tail close enough to take the victory during the final 40/50 metres.
Even for someone with a history in 400m running, that extra bend and straight would be incredibly alien to the 32-year-old who would be facing someone accustomed to sprinting through the pain barrier. Simply put, over 600m, Bolt's pace would be diluted to an extent that Farah's indomitable fitness would prevail.
Bolt just isn't Bolt when you sextuple the distance.
How do you think would win over 600m - Bolt or Farah? Have your say in the comments section below.