Whitehaven have criticised the RFL over the situation that saw former captain Marc Shackley handed a four-year ban after failing a drugs test.
Shackley, 33, retired from rugby league last September after making 236 appearances for Workington Town and Whitehaven.
He was limited to just seven in 2021 through a knee injury which caused him to hang up his boots.
It was announced by the UK Anti-Doping Agency this week that he had failed an out of competition test and is banned until October 2025.
The player said he had taken a fat burner containing a trace of clenbuterol, an anabolic agent, to slim for surgery on the joint.
He could not prove the violations were unintentional and the ban imposed, backdated to October 8 2021.
Club statement on Marc Shackley
A Whitehaven club statement said: “Marc Shackley was tested in a out of competition test after he had informed the club he had retired from the game. All the evidence from the club, player, doctors and physios are in his favour; but the issue arose as you can be tested by UKAD up to 12 months after your contract finishes or you(r) retirement from the game.
“The club as well as Marc did not know about this rule as this has never been explained in any pre-season meetings with the RFL.
“Over the years in competition, Marc has taken at least one test a year and passed them all.
“We see the RFL have now made a rule that retiring players have to inform them of retirement. This was never in place for Marc and seems to have been brought out after this case.
“We would just like to thank Marc for everything he has done for this club over the years.”
Shackley was captain of the Whitehaven team that won promotion to the Championship as League 1 champions in 2019.
The operational rules state that the RFL should be informed when a player retires, either by the player himself or the club when submit a list of departing players.
Shackley was not on the list submitted by Whitehaven last year, the RFL has said.