THE "EASIEST" tackling case Match Review Officer Michael Christian has assessed was Nic Naitanui's.

The West Coast ruckman has been offered a one-match ban for his tackle on Port Adelaide's Karl Amon.

Amon was left concussed after the incident at Optus Stadium on Saturday afternoon, and the Eagles will fight the charge.

There has been plenty of debate around Christian's decision to ban Naitanui, but the MRO told Melbourne radio station SEN on Tuesday it was a simple decision to make.

"Tackling is the most challenging part of this role, because it's obviously something you're allowed to do. But this one, for me, was the easiest that I've had to adjudicate on, because the rules around tackling are pretty simple in a sense: if a tackle is unreasonable in the circumstances," Christian said.

"Now that's the broad definition but when you nail it down, and the particular application here is where an opponent is driven into the ground with excessive force, particularly when the player tackled is in a vulnerable position, then that constitutes unreasonable in the circumstances, which is rough conduct, which is a charge.

"Once we determined that, then it's a question of impact. We've fined a number of players this year for dangerous tackles where the player has been able to get up after, you know, 10 seconds and play out the game or maybe go off for a minute and then come back on the ground, where that impact is low.

"In this particular case, considering the medical report from Port Adelaide, the impact was medium rather than low, hence the one-match sanction."

Eagles coach Adam Simpson was confused by the situation when he spoke to Channel Seven on Monday night.

"It's a bit of a head-scratcher for me, personally," Simpson said.

"The vision I saw, he didn't have his arms pinned."  

Naitanui will face the Tribunal on Wednesday night after the Eagles were granted a day's extension as their lawyer David Grace QC was interstate and unable to reach Melbourne in time for Tuesday's hearing.

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