Bridge authorities should look at the sport's "totally unsuitable" anti-doping rules after world number one Geir Helgemo was banned for a year, says the Monaco Bridge Federation.
Helgemo, who is Norwegian but represents Monaco in the card game, tested positive for banned substances Clomifene - a female fertility drug - and synthetic testosterone.
His ban will expire on 20 November.
The Monaco Bridge Federation said it "regrets" Helgemo's sanction.
"Experience shows that anti-doping regulation cannot be applied without discernment to the brain sport of mind games," the federation's president, Gilbert Vivaldi, told BBC Sport.
"Do you think testosterone levels can seriously influence intellectual performance?
"We regret that a talent such as Geir Helgemo is sanctioned under an anti-doping regulation that is certainly adapted to physical sport but totally unsuitable for brain sport.
"We hope that this event will prompt interested authorities to look into this problem."
Helgemo, 49, provided the sample at the World Bridge Series in Orlando in September, and previously accepted a provisional ban, to which his suspension has been backdated.
Kari-Anne Opsal, the president of the Norwegian Bridge Federation, said the drugs were "not performance enhancing".
In a statement, she said: "Geir Helgemo has previously played for the Norwegian national team and is our biggest star. Many within the bridge community know Geir and respect him.
"It is his responsibility not to take substances that are on the doping list, even though in this instance they are not performance enhancing in bridge.
"I feel for Geir in this situation and hope he will come back stronger after 20 November, 2019, when his ban ends."
Helgemo is not the first bridge player to be found using banned substances. The World Bridge Federation is recognised by the International Olympic Committee and as such abides by World Anti-Doping Agency (Wada) rules.
In 2015, Wada figures showed 3.6% of bridge players had returned adverse analytical findings.
In 2017, Helgemo and world number two, fellow Norwegian Tor Helness, 61, were both convicted of tax evasion.