Collingwood football chief Graeme Allan has fallen on his sword, resigning his post shortly after being banned by the AFL for his part in the Whitfield affair.

The AFL confirmed on Tuesday that Greater Western Sydney’s Lachie Whitfield will serve a six-month ban for trying to avoid a drug test.

AFL chief executive Gillon McLachlan also announced that former Giants officials Craig Lambert and Allan had both been banned for 12 months for their roles in the controversy.

But the league is yet to decide whether GWS will be penalised with a loss of draft picks.

The trio were investigated after Whitfield spent three days at Lambert’s house, with the knowledge of Allan, in May last year in an alleged bid to avoid a possible drug test, which is a violation of the anti-doping code.

“I think people are always disappointed in individuals who make mistakes and this is a poor reflection on them, clearly,” McLachlan said of the conduct of Allan and Lambert.

“I would say (it’s) a mistake that’s hard to believe.”

Allan, who was only appointed Pies’ football boss in August, maintained his position that he was simply trying to help Whitfield through a messy relationship break up.

“I accept that I made an error of judgement in the way I dealt with Lachie Whitfield’s personal relationship issues and I have agreed to pay the price for it,” Allan said via a statement.

“There was no dark intent or other agenda behind what transpired in 2015. I reject any claim or speculation to the contrary.”

Whitfield will be barred from using GWS facilities for four months before returning to train for the final two months of his ban while not being allowed to play.

The suspension effectively rules him out for just eight AFL matches, but McLachlan defended the severity of the penalty.

“He’s a 19-year-old kid who took advice from his supervisors, the people who were looking after him, so there’s a different allocation of responsibility,” he said.

“There’s not one piece of evidence or any allegation of anything to do with performance enhancing drugs.

“He didn’t specifically get asked to do a test that he skipped … there has clearly been a breach of the anti-doping code but I think it’s significantly different than when we’re talking about actioning allegations of any impropriety that involves performance enhancing drugs.”

McLachlan said the penalties had been arrived at in consultation with ASADA.