Audley Harrison believes it would be very difficult for a professional boxer to compete at the Rio Olympics "from an infrastructure point of view".
The sport's governing body, the International Boxing Association (AIBA), voted on Wednesday to make a rule change allowing professionals to compete in this summer's Games.
However, wildcards would not be handed out to any interested pro boxers and they would have to pursue qualification at a tournament scheduled for Venezuela in July.
This is one of the factors Harrison claims will deter a lot of the big names of the boxing world.
Harrison, who won gold at the Sydney Olympics in 2000, told BBC Radio 5 live: " When you look at amateur boxing now, the line has been blurred to some degree because you now have amateur boxers boxing without head guards, basically punching for pay with the world sports programme that they are doing.
"So you have this already moving towards the professionals - they are doing five-minute (five three-minute) rounds, the head guards are gone and they are being paid, so what you've got to think about is (the) two sports are very different sports.
"Professional boxing and how you train for a professional boxing contest, 12 rounds, three minutes, and the Olympic cycle where you are fighting maybe four times over 10 days is a totally different sport.
"I think it's more smoke and mirrors from Dr (AIBA president CK) Wu in terms of announcing they can do it because you have to go through a qualifying process to qualify for the Olympics - all of the amateur bodies are a part of that - and it's only two more tournaments.
"One's coming up on June 16 until the 25th and the other one is July 3rd until the 8th, so I just don't think it's plausible that a professional boxer is going to be able to change his training dynamic to go and try and qualify for that tournament.
"They've already said that no boxer is going to be allowed in on a wildcard, like Manny Pacquiao or some of the most high-profile professionals, so how are they really going to train for those tournaments coming up?
"I think it's set the cat amongst the pigeons, we're all talking about it, but the reality is, from an infrastructure point of view it can't be done, it can't be done."