Carlton have sacked first-round AFL draft pick Josh Bootsma, with his inappropriate use of social media proving the last straw for the Blues.

The Blues said the 21-year-old had been struggling with discipline issues for several months.

But Bootsma's fate was sealed on Monday when the club was made aware of the social media problem.

Blues football director Andrew McKay would not go into what happened, but several media outlets reported it involved explicit images.

"The point is, he's put something on social media that's highly inappropriate and it really does not meet the standards of the football club," McKay said.

Carlton said they spoke with Bootsma's manager and the AFL Players Association before sacking him.

But McKay said senior players were not consulted.

"The decision was made by management at the football club and you have to understand we acted quite swiftly and we needed to," McKay said.

Asked if Bootsma had lost his teammates, McKay said: "to be honest, yes he had.

"He was endeavouring to gain that back over the last few months - it's been going on for probably a year now.

"It's disappointing, we've been getting Josh some help in this regard.

"But he continues to not uphold the standards we require."

McKay said Bootsma was regularly late for training and missed other club appointments.

The Blues said in a statement that they were axing Bootsma for breaching the club and AFL codes of conduct.

"The club has attempted to offer Josh numerous forms of welfare and support in recent times, however he has continuously not lived up to the standards expected of a senior listed AFL player," McKay said in the statement.

"This latest issue has left the club with no other choice but to take this course of action."

McKay added Carlton players and staff were briefed on social media and the AFL code of conduct.

It is also understood that Bootsma's partner is about to give birth.

Bootsma has not played any senior games this season.

Taken at pick No.22 in the 2011 draft, the utility had played 14 senior games in 2012-13.

Bootsma had a contract with the Blues until the end of next season.

Carlton said they would continue to offer him counselling and welfare support.

He is the third player to leave Carlton this season, with Nick Duigan and Heath Scotland retiring.

Two years ago, Carlton midfielder Brock McLean was fined $5000 for comments he posted on Twitter.