JOHANNESBURG – Exercise physiologist, Zac van Heerden, says it will be very difficult for Aphiwe Dyantyi to win any kind of appeal after the Springbok and Lions wing was found guilty of doping on Friday.The 25-year-old tested positive for “multiple anabolic steroids and metabolites” and faces up to four years out of the game because of the offence.Speaking to 702’s Buhle Madulini on Sports Talk on Friday night, Van Heerden said it will be extremely difficult for Dyantyi to prove his innocence.“The only way he will be able to get any relief is if the medical team of the Springboks or of the Lions, possibly a private medical company, registered with the health professional council, come forward and say they supplied him with a protein supplement to help him recover quicker and to their knowledge it did not contain any banned substances”, he said.“They could try to prove beyond any reasonable doubt that Dyanti accidentally used a banned substance, but the appeal bar has been set really high, so you really have to go to enormous lengths to prove your innocence. I personally think that’s not possibly in this case”, he added.Van Heerden said that players themselves are held fully responsible when something like this happens.“Players are fully aware of the dangers of taking supplements and they are continually briefed on how careful they need to be. If something goes wrong it is on their head”.Dyantyi was provisionally suspended after SAIDS (South African Institute for Drug-Free Sport) informed him of an adverse analytical finding.Dyantyi denied any knowledge of taking a banned substance at the time.“I want to deny ever taking any prohibited substance, intentionally or negligently, to enhance my performance on the field. I believe in hard work and fair play”, he said in a statement.The 2018 World Breakthrough Player of the Year then exercised his right to have a B-sample tested.That sample confirmed the A-sample results of the presence metandienone, methyltestosterone and LGD-4033.On Friday, SAIDS released a statement saying that these performance-enhancing substances are on the 2019 List of Prohibited Substances and Methods in Sport, and are banned in-and out-of-competition.Dyantyi has the option of admitting to the charge and accepting an appropriate sanction based on the World Doping Code’s framework.He may also submit a plea for consideration of a reduced sanction by providing mitigating circumstances.SA Rugby also released a statement on Friday saying that it, along with the Lions Rugby Company and Dyantyi are “working with SAIDS, the World Anti-Doping Agency (WADA) and all other relevant authorities on the matter.”