The British marathon record holder Steve Jones fears Mo Farah will always be tainted by his association with Alberto Salazar – and says he wishes he had left his former coach years ago.

Jones fully expects Farah to shatter his 33-year-old UK record of 2hr 7min 13sec during the London Marathon on Sunday and even thinks his fellow Briton could challenge for the world record one day. But he does not understand why Farah decided to stay loyal to Salazar’s Nike Oregon Project training group until 2017, two years after they started to be investigated by the US Anti-Doping Agency – an investigation that continues.

Mo Farah splits with controversial coach Alberto Salazar and returns to UK Read more

“Personally, I would have distanced myself,” Jones said. “I said that three years ago when this whole thing blew up about Salazar. The people at Portland thought I was telling Mo to quit Salazar and get away as far as possible. I was just saying distance yourself until it either all falls back into place or the stories became true.”

Jones, who is now a distance coach in Colorado, said he was well aware of Salazar’s reputation for pushing himself to the limits since he began racing him during the 80s. “We have had some times together and I know his abilities,” he said.

“I know he is a little crazy. In marathon we are all nuts and raisins. It is what level you are. Alberto always takes things to the nth degree. I think that is what he has done with his coaching and his training.”

Jones said Salazar’s well-publicised health problems – his heart stopped for 14 minutes in 2007 – may have been a consequence of driving himself too hard. “That is what happens when you overdo things. I mean this is a little unfair to be talking about all this when we’re talking about Mo. I’m not trying to say this is the avenue Mo is taking, or anything, but there is a little taint there. It is guilt by association, I suppose, which is very unfair.”

Farah, who has always strenuously denied breaking any rules, is now coached by Gary Lough since quitting the track last year. Salazar has also consistently denied any wrongdoing after the BBC and ProPublica alleged he had broken anti-doping rules in 2015.

The 62-year-old Jones is delighted his marathon record is finally being challenged and is confident he will be bidding it a fond goodbye on Sunday. “I never thought the record would last so long. It is surprising. Although when I did it I kind of blew up in the last five or six miles so it could have been a little quicker had I not been so aggressive early on.

“When I look at my 2:07 I’m really looking at 2:05 but it’s good to see it being challenged now. I should just wave the white flag now and hand it over. I was confident in 2014 it would go, although when Mo went from talking about winning the race to breaking my record it made me think he wasn’t quite so confident. This time it’s a foregone conclusion – even a bad run this time should break the British record.”

The forecast of 23C for Sunday is likely to scupper the plans of the Kenyan Eliud Kipchoge and the Ethiopian Kenenisa Bekele to challenge Dennis Kimetto’s world marathon record of 2:02:57 set in 2014.

Kipchoge ran 2:00:25 in Monza last May, but it did not count as a new best under IAAF rules because he was helped by a phalanx of pacemakers who subbed in and out of the race. However he believes he is capable of taking on Kimetto’s time at some point. “Personally I know that one day I will break a world record,” he said. “It might be too hot on Sunday but everyone is running in the same weather. I promise we will see a beautiful race.”

Kipchoge’s coach, Patrick Sang, said his man was in very similar shape to his epic run in Monza when he came so close to being the first man to run under two hours – albeit with extra help. “But the heat, of course, will have an effect,” Sang said. “To what degree, I don’t know, but it will have an impact.”

When asked whether there was still a hope of a world record on Sunday, Sang nodded before replying: “If the temperature comes down a little bit there is a big chance.”

Unfortunately for Kipchoge and Bekele the increasingly certain weather forecasts suggest that chance is dwindling by the hour.