Former journalist Mike Sheahan has finally conceded that Collingwood must relieve coach Nathan Buckley of his duties after another poor display from his side.

The Magpies fell to 15th on the ladder after their 23-point loss to Carlton on Saturday, which came less than a week after a brilliant victory over a Geelong side who went into that clash at 5-0.

Carlton led at every change to leapfrog their rivals on the ladder, and Sheahan said the result should be the last straw for the club.

“On Saturday night I must say, and I’m a really big Buckley fan personally…but I think it’s a question now of not if, but when with Bucks,” Sheahan said on SEN Breakfast on Monday.

“I think Bucks is gone as coach of Collingwood.”

While host of the breakfast show Tim Watson thought Buckley would hang on to his job until the end of the season before being let go, co-host and former Melbourne captain Garry Lyon had other ideas.

Lyon admitted it wouldn't make sense for Buckley to stay at the club on borrowed time, and should step away from the role as soon as the club decide he's not the right man for the job.

“When you go, you go surely,” he said.

“When either you decide, or the club decides, you go. It’s no good dagging around. Why would you dag around?

“If the club or the coach comes to the conclusion that he’s no longer going to be there beyond the end of the year, then the time is to go.”