Double Olympic gold medallist Kelly Holmes said there will always be "a cloud" around Mo Farah's achievements due to his association with coach Alberto Salazar.
Salazar was banned from athletics for four years in October for multiple anti-doping violations - a decision he subsequently appealed. The Court of Arbitration for Sport will hear that appeal in the spring.
The 61-year-old American was sanctioned along with endocrinologist Jeffrey Brown for "orchestrating and facilitating prohibited doping conduct" while working with the Nike Oregon Project (NOP), which was established in 2001. Great Britain's four-time Olympic champion Farah trained there between 2011 and 2017.
Farah has subsequently said he has 'no tolerance' for anyone who breaks the rules.
Holmes, who won 800m and 1500m golds for Great Britain at the 2004 Athens Games and 800m bronze at the 2000 Sydney Games, believes anyone who's ever been associated with Salazar will always have to deal with the negative connotations of that connection.
"There's always going to be a cloud whilst his coach has got these issues surrounding him," Kelly told RTÉ 2fm's Game On when asked about Farah's achievements.
"The coach had a lot of athletes, and all of those athletes - and any athletes that have been involved with him - are also going to have a cloud over their heads.
"Something needs to happen to put this to bed in one way or another. You’re never going to get away from a cloud when you have been coached by somebody who’s now been banned by the sport and has this over his head."
"The cheats are ahead of the game. The scientists are ahead of the game."
Holmes called for a zero-tolerance approach to doping, suggesting lifetime bans and greater accountability are essential in the fight against cheating.
"It shouldn't even be in your psyche to think that (doping) is a good way to go," she said.
"If you take that risk then I'm sorry, you're out.
"Doping in sport, right across the board, not just athletics - you look at weight lifting, you look at so many sports - it has to be stamped out.
"There needs to be a no-tolerance policy, there needs to be higher bans, higher sanctions, so that people don’t take those risks. Otherwise we’re going to always be on the back foot.
"There’s a wider issue here. There’s too much greed in sport. You’ve got agents that are corrupt; you’ve got doctors that are corrupt; you’ve got people selling the products and then the team around an athlete. An athlete, or any sports person, might get coerced into the sense of, 'this is what everyone does to be good’.
"If you have an athlete and they declare the team around them - their physios, their coach, training partners - you as a group are then accountable for it. That would make other people around you go, 'hold on a minute, I don't agree with what you're doing, I'm getting out of here because that's going to ruin my reputation'.
"If you're all squeaky clean, 100%, then you shouldn't care that all your team sign a declaration to say, 'yeah we're all accountable for anything that goes wrong'.
"Unless we start doing this, people are going to get away with it.
"The cheats are ahead of the game. The scientists are ahead of the game. We've got to start realising that this isn't (a case of) just one person going, 'you know what, I want to run faster'."
