Tyson Fury and his cousin Hughie are set to claim they failed drugs tests after eating vast amounts of contaminated offal,
Charges against the cousins will be heard by the United Kingdom's National Anti-Doping Panel next month, with the Fury camp thought to be confident of avoiding bans.
The pair will argue they unwittingly tested positive for a banned steroid because they eat a whole boar, including its internal organs and entrails, between them each week.
The Furys - Hughie, 22, and Tyson, 28 - strenuously deny using drugs to boost performance. Their legal team will argue that eating the liver of an animal that has been fed steroids to enhance its growth can leave traceable amounts in a human body. A farmer is set to testify that the Furys buy a boar from him each week.
The case has been protracted, with both heavyweight boxers provisionally suspended on June 24 last year after failing tests by UK Anti-Doping.
The ban was lifted in August ahead of an NADP hearing, which is scheduled to finally take place next month.
Peter Fury, the pair's trainer and Hughie's father, could not comment due to the ongoing legal proceedings. UKAD director of communications Emily Robinson said: 'UK Anti-Doping is unable to comment on ongoing cases.'
There are precedents for the Furys' planned line of defence.
Tong Wen, an Olympic gold medal-winning judoka from China, blamed pork chops when she tested positive for the steroid clenbuterol in 2009. She was cleared due to 'procedural failure' in the laboratory tests.
A year later cyclist Alberto Contador cited a beef steak as the cause of clenbuterol traces being found in his system, but the Spaniard was banned by the Court of Arbitration for Sport in 2012.
In December 2011 UKAD issued a warning advising athletes against eating liver due to the small risk of returning a positive clenbuterol sample if the meat was contaminated.
Tyson Fury has not fought since becoming world champion by beating Wladimir Klitschko in 2015. Last year he cited an injured ankle when pulling out of a rematch against Klitschko on the day UKAD suspended him for the positive test.
He vacated his WBO and WBA titles due to ill-health and the next day the British Boxing Board of Control suspended his licence. But this week Fury announced plans to return to the ring in July and he has started training in Marbella.
On Sunday Hughie Fury pulled out of his title fight against WBO heavyweight champion Joseph Parker with a back injury.