THE AFL has sent 'please explain' notes to North Melbourne and Geelong after Drew Petrie, Majak Daw and James Kelly took to Twitter to condemn the four-match suspension handed to Kangaroos midfielder Jack Ziebell.

In the hours after Ziebell's suspension was upheld by the Tribunal, Petrie tweeted: "Lost enough sleep already tonight over that decision. Got a sore neck from shaking my head so much. Time for bed."

Petrie then decided to send one more tweet before he nodded off.

"Advice for @jackziebell. Stop being so courageous and playing footy hard the way it's meant to be played. Please turn into a softy!"

Meanwhile, Kelly tweeted: "I was going to tweet how Ziebell getting four weeks was a mare of a decision but decided not to so I don't get in trouble #smartkell … smart"

However, the AFL has confirmed that the 'please explain' note sent to North Melbourne does not apply to the comments made by its chairman James Brayshaw.

Speaking on Triple M on Wednesday, Brayshaw said: "I think it was an incorrect decision to find him guilty.

"If you're playing football, surely you should be encouraged to go for the ball when it's in your area and not be penalised when you do, so that's where the groundswell comes from.

"It worries me when the tribunal [is] trying to steer footballers away from attacking the ball."