South Africa internationals Bjorn Basson and Chiliboy Ralepelle are free to play rugby again after they were exonerated for testing positive for a banned substance.
Basson and Ralepelle were found to have methylhexaneamine in their systems during the autumn tour of Europe.
The Bulls duo were immediately suspended and sent home ahead of an investigation into the results.
However Basson and Ralepelle have been cleared of any wrongdoing after a panel found they had taken the substance unintentionally.
It is believed methylhexaneamine was in a supplement that the players had been taking and was thought to be safe after it had been used in the past.
As well as clearing both players, the three-man disciplinary panel admonished the South African Rugby Union (SARU) for not having the supplements tested more comprehensively.
SARU chief executive Jurie Roux offered an apology to Ralepelle and Basson.
"This verdict completely quashes any idea that either the players or the team were guilty of any attempt to cheat. No responsibility attaches to the players at all," Roux said.
"The banned stimulant was in a supplement given to the players in the warm-up before the Test against Ireland and is a product that has been used by the Springboks before - without any adverse analytical findings - and is used by other professional and national teams in both hemispheres.
"It was manufactured in the UK and was tested at SARU's request by one of only two laboratories in the world equipped to perform the necessary protocols in order to ensure that it complied with the requirements of the World Anti-Doping Authority (WADA).
"That the players subsequently tested positive for a banned stimulant was an enormous shock to the Springbok team, management and to SARU, and I am most sorry that the players have had to endure the stress and stigma attached to a failed dope test.
"Hopefully this verdict will have laid to rest any idea of any wrongdoing on their part."
SARU's medical manager Clint Readhead insisted everything had been done to ensure the supplements provided to players were safe and clean.
As a result of this incident, South Africa will no longer use supplements.
"We have always been wary of supplements but have tried to manage the risk as the players do want to use them," said Readhead.
"We did everything in our power to ensure that the supplements we supplied to the players were safe and we thought we'd put in place enough safeguards to minimise that risk.
"We received a certificate from the lab saying that the product met WADA specifications.
"As a result of these positive tests however we will not endorse, condone or supply supplements to any of our players as one positive test from a rogue batch is too heavy a price to pay."