Nyhuis pleaded guilty to rough conduct and the three-man tribunal jury took two minutes to confirm the penalty.

Also on Tuesday night, Adelaide star Bryce Gibbs was found not guilty of rough conduct.

Gibbs had risked a $3000 fine by going to the tribunal.

AFL advocate Jeff Gleeson, Nyhuis' advocate Andrew Tweedie QC and tribunal chairman David Jones had all agreed that three games was the appropriate penalty for Nyhuis.

Gray could recover in time for Sunday's big home game against GWS.

The tackle sent Gray's head slamming into the ground in the third quarter on Sunday at Optus Stadium and he did not return to the game.

"In any view, that could have been a different situation because of the force (of the impact)," Gleeson said.

Nyhuis' charge was a direct referral to the tribunal, meaning the penalty was entirely up to the jury.

Tweedie said Nyhuis did not deserve more than three matches, noting that would be a major penalty to a 10-game player in his second AFL season.

He added Nyhuis was extremely remorseful and had apologised personally to Gray post-match.

Tweedie said it was not a spear tackle and Nyhuis was unlucky because the pivot motion put Gray off-balance.

Instructing the jury, Jones said there was "considerable merit" in a three-game ban.

Earlier, Gibbs successfully argued his case following an incident where he bumped Geelong captain Joel Selwood off the ball during Thursday night's win over the Cats at Adelaide Oval.

The Crows midfielder could have accepted a $2000 fine, but opted to challenge the charge.

Selwood and opponent Riley Knight were jostling when Gibbs laid a block on the Cats skipper.

Selwood went to ground and the Geelong medical report said he had a knock to the jaw, but will not miss any games.

"If I was to bump him, I would have lowered my centre of gravity and there would have been more force," Gibbs said.

Gibbs' advocate Andrew Culshaw said the player took a brace position and did not contribute to the contact.

"This doesn't pass the sniff test ... being headbutted on the shoulder isn't rough conduct," Culshaw said.

In contrast to the straightforward Nyhuis hearing, the jury took 13 minutes to find Gibbs not guilty after an hour of evidence and arguments.

"I was a little bit (surprised it took so long)," the club's Twitter feed quoted Gibbs as saying.

"It's my first time doing something like this at the tribunal so I did think it would take a little bit quicker, but glad it all went well."

Australian Associated Press