DEFENDER James Sicily will miss Hawthorn's round six clash against St Kilda after pleading guilty to a serious misconduct charge at the AFL Tribunal on Tuesday night.

Sicily told reporters after the hearing he was disappointed in the result but more so in his actions, which saw him referred directly to the Tribunal for standing on North Melbourne forward Shaun Atley's lower leg at Etihad Stadium on Sunday. 

"(I'm) disappointed in myself that I guess I've done an undisciplined act and that's something that I need to get out of my game," Sicily said.

"It's definitely something I've learned from this whole experience." 

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Sicily's legal representative, Peter O'Farrell, had earlier told the Tribunal his client had been "admonished" by Hawks coach Alastair Clarkson and football manager Graham Wright for his lack of discipline.

"Like me they were disappointed in what happened with my actions, but they've still got my back in a sense and they still want me to do well," an emotional Sicily said after the hearing. 

Sicily was referred directly to the Tribunal by Match Review Officer Michael Christian after he stood on Atley's leg during the second quarter of Sunday's game while the Kangaroo was lying on the ground face down.   

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Sicily entered his guilty plea after discussions between O'Farrell and the AFL's legal counsel, Jeff Gleeson GQ, before the Tribunal hearing started.

Gleeson submitted that the Tribunal should give Sicily a one-match ban given the Hawk had pleaded guilty rather than trying to have his charge downgraded to misconduct. 

The Tribunal jury members Jason Johnson, Richard Loveridge and Shane Wakelin deliberated for just one minute before handing Sicily a one-match suspension. 

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Gleeson said Sicily had glanced at the nearest umpire before standing on Atley. Once he had seen that umpire was "otherwise engaged", he had committed his offence, an approach Gleeson argued indicated "a slightly calculated approach to what followed". 

North's medical report was tabled and indicated Atley had required no treatment after the incident. 

But Gleeson argued this was due more to "good luck than good management", characterising Sicily's conduct as "a pretty risky act".

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