GREATER Western Sydney forward Jeremy Cameron has been suspended for four matches for his high bump that left Brisbane Lions draftee Rhys Mathieson with a broken cheekbone.

Cameron's case was referred directly to the Tribunal on Monday after the Match Review Panel graded it careless with severe impact to the head.

The 21-year-old pleaded guilty to the charge as classified by the MRP and will be sidelined for matches against Melbourne, Geelong, the Sydney Swans and Port Adelaide.

Cameron, who appeared in person on Tuesday, said he sought Mathieson's phone number immediately after the NAB Challenge match to check if he was OK.

Mathieson, who will miss up to six matches following surgery on Monday, told him it was "just another day at the office". 

Essendon defender Courtenay Dempsey was the last player found guilty of a charge classified as severe impact, in round 22 last season. He also received a four-game ban. 

There have been fewer than 10 cases with that maximum impact grading since the Tribunal system was overhauled in 2005.

Cameron's case focused on his inability to avoid contact to Mathieson and his insistence that he did not leave the ground to bump his opponent. 

He told the Tribunal it was too late to pull out of the contest once Mathieson fired off a handball and he braced for contact as the Lions teenager moved towards him.

His legal counsel, Tony Burns, suggested a three-match penalty reduced to two weeks with an early guilty plea would be appropriate because it was at the lower end of severe impact bumps.

Burns said anything above a final penalty of three matches would be "manifestly excessive".

AFL counsel Jeff Gleeson used frame-by-frame footage to show Cameron did leave the ground once contact was made to Mathieson.

As well as Cameron's early guilty plea, the Tribunal members were directed to take into account the risk of serious injury to Mathieson, which allows them to upgrade the final penalty.

"I accept the sanction they have handed down to me and I just hope Rhys Mathieson is OK," Cameron said as he left AFL House on Tuesday.

"I just want to move on with my season now. We just wanted to go in there and plead my case."