Britain's Mo Farah can claim to be the greatest distance runner in history if he can pull off a second Olympic double. Ralph Ellis looks at the challenge ahead.
"The big challenge is going to come from the Ethiopian trio of Hagos Gebrhiwet [17.5], Dejen Gebremeskel [24.0] and Muktar Edris [20.0] who plan to gang up together to force the pace. Their aim is to set off at close to world record time and run the legs out of Farah."
I did Parkrun on Saturday morning and absolutely smashed Mo Farah's time. Finished more than a minute quicker. Ok, so he was running 10,000 metres in the Olympic final and I did only 5,000, but who's arguing about details like that?
Seriously, it's when you finish off your own little run, puffing and panting, then realise Farah does the same thing twice as fast that you understand the sort of level the elite guys have reached. And in Mo, we're talking about the elite of the elite.
Any ordinary mortal might have laid on the track feeling sorry for himself after getting tripped in the early stages of the 10,000m. Mo simply bounced straight back up, ignored any pain from a gash on his shoulder from somebody's spikes, and stayed with the field before producing an astonishing turn of finishing speed to take gold.
I was looking back on a column I wrote in the middle of the London Olympics, when he'd won the first of his two gold medals and I was recommending to back him at [2.2] for the double. He ultimately won the 5,000m so comfortably on a glorious Saturday evening in London it's impossible to think he was bigger than even money to do it.
You won't get those odds now. Mo, beginning the heats in Rio today for the 5,000m, is as short as [1.2] to collect the gold medal. He's won every major race over that distance since September 2011 and it seems layers are just as scared of his prowess as his opponents.
If you want huge odds, then have a look at the market for a world record to be broken when the final is run at 01.30 on Sunday morning and odds of [28.0] or better.
The odds are big because a world record is a tall order. It currently stands at 12:37.35, set in 2004 at a meeting in Holland by Ethiopia's Kenenisa Bekele - who then set the Olympic record four years later at 12:57.82. Mo's current personal best is 12:53.16, but he may have to go well inside that time to get his gold.
The big challenge is going to come from the Ethiopian trio of Hagos Gebrhiwet [17.5], Dejen Gebremeskel [24.0] and Muktar Edris [20.0] who plan to gang up together to force the pace. Their aim is to set off at close to world record time and run the legs out of Farah to see whether he has properly recovered from his first gold.
It's a challenge that Mo is expecting. "I wouldn't be surprised if they are told to go as hard as they can to tire me out," he has said.
Only Lasse Viren has ever achieved the double double, way back in 1972 and 1976, and all the evidence suggests he did it with the aid of blood transfusions which were legal then but are banned now.
But Farah has the class to do it clean, and he can then be considered the greatest ever.
I'll feel even more proud of my Parkrun time!