Mo Farah is feeling hurt, and a little bit annoyed. They are not emotions he is familiar with after two years of extraordinary success on the track but dark mutterings that he has changed from national treasure to national treasure-hunter by accepting a huge appearance fee to run just the first half of the Virgin London Marathon in April are, he says, unfair and untrue.
The allegation, according to some media reports last week, is that the double Olympic champion is cashing in on his celebrity by signing for a whopping pounds 750,000 for what amounts to no more than publicity stunt in this year's race before he returns to London next year for his full marathon debut.
Farah insists the thinking behind his 'half a race' is to learn about the London course and ease his transition to the full 26.2-mile distance in 2014 without compromising his track ambitions at this summer's World Championships in Moscow. And he adds that the quoted appearance fee is "crazy".
"I'm not going to say what it actually is, but the figure is wrong," he said. "The day when I'm just taking the money to do this or do that is the day when I won't be feeling 100 per cent in my heart. If it came to that, it would be wrong.
"I've had some criticism, which would be fair enough if, as an athlete, I went from race to race and said to myself, 'I'm just going for a bit of dough'. But I'm not doing that. Yes, there are bigger financial rewards than track and field if you go to the roads. We all know that. But I'm not doing it because of that. It's because when I come out in 2014 for the marathon, I want to be able to attack it knowing that I've had as much practice as I can."
That practice begins today when Farah goes to the start-line for the Rock 'n' Roll New Orleans Marathon and Half-Marathon - a noisy and vibrant event for the thousands of fun runners who will be serenaded by rock bands along a route that takes in the city's historic French Quarter but a deadly serious one for Farah as he embarks on his journey from track to road.
His aim, he says, is simply to win against a high-class field that includes Kenya's three-time London Marathon champion, Martin Lel, and 2010 New York Marathon winner Gebre Gebremariam, of Ethiopia, but he also has his eye on breaking Nick Rose's 28-year-old British half-marathon record of 61min 03sec.
Farah has actually covered the 13.2-mile distance faster than Rose, clocking 60-23 in his only other half-marathon outing in New York in 2011, but his time could not be ratified as an official record because of the course's downhill gradient. The New Orleans race is flat and therefore legal for record purposes. Having opened his season with a 3,000 metres win in Birmingham last week, Farah has had only a few days to reacquaint himself with his wife, Tania, and young family in Oregon before flying to New Orleans, though it was long enough to realise that long-distance running is a lot easier than childcare. With his wife ill, Farah had the task of cooking and getting the children ready for bed one evening and he admits he failed miserably.
It is with some relief that he is back doing what he does best this weekend, and with plenty of high-altitude mileage in his legs from his recent two-month training camp in Kenya, Farah does not rule out a sub-60min time today.
"I think anything is possible if the other guys go out quick," he said. "I'm not afraid to go with them but I'm not going to go out there to set the pace. That's what my coach tells me. Just win the race and the time will come."
Farah admits he has plenty to learn about racing on the roads, including the art of knowing when to take a drink and the mechanics of grabbing a water bottle while running at speed.
In the New York City Half-Marathon two years ago, Farah's first race after joining up with American coach Alberto Salazar, the weather was so cold that he managed to get to the finish without any liquid refreshment but the warm, humid conditions in New Orleans mean that this time he will have no choice but to make use of the drink stations.
It is, Farah admits, a voyage into the unknown, and even if he succeeds at the half-marathon distance there is no guarantee that he will be capable of the 2hr 4min time that he will need to match the world's best marathon runners.
"I'm really excited because I don't know what I'm going to do," he said. "It doesn't mean that I'm going to be the best at it. Look at [Zersenay] Tadese. He's the half-marathon world record-holder but he's never really achieved at the marathon. But I'd like to give it a good go. It's something you've got to try."