Leigh forward Sam Barlow has been given a four-year ban for obstructing a doping control officer, the Rugby Football League has announced.
The 28-year-old prop, who played for Scotland in the 2013 Rugby League World Cup, is accused of intentionally disrupting the drug-testing process when a UK Anti-Doping (UKAD) official visited his home in July 2015.
An independent national anti-doping panel found Barlow guilty of "tampering or attempted tampering with any part of doping control" and, although the player contested the decision, it was upheld on appeal.
"The outcome of this case sends a clear message that we will not tolerate obstructive or threatening behaviour towards any of our personnel," UKAD chief executive Nicole Sapstead said.
"Whilst incidents such as this are rare, the obstruction of the doping control process in any way is, and will be, taken very seriously.
"Our role is to deter and detect those who cheat the system and protect everyone's right to clean and honest sport.
"We cannot do this on our own and we ask all athletes, support staff and even family members to work with us to support the testing process so we can continue to protect the very essence of sport - fair play."
Barlow, who has also played for Sheffield Eagles, Featherstone and home-town club Halifax, is banned from all sport until November 2019.
He was also subject to criminal proceedings relating to the test attempt and, in May, pleaded guilty to common assault at Bradford Crown Court.
Barlow maintained his innocence and intention to overturn the ban in a statement.
"In relation to the news and press coverage this morning, I will be making no comment alongside my family so please respect our wishes until the high court appeal has been lodged.
"I remain in the position I am innocent and in no way, shape or form have I failed, refused or avoided a test.
"No further comments will be made until my barrister and lawyer agree the time is right."
