Port Adelaide's Charlie Dixon's second appeal of the three-game ban for his rough conduct charge on West Adelaide's Jordan White has failed again.

Dixon will be unavailable for selection for the next three games after failing to have a suspension overturned by a SANFL appeals hearing.

The key forward initially pleaded guilty to the charge but hoped to lower the level of impact from severe to high, which would ultimately downgrade the penalty from three to two weeks.

The incident was graded as careless conduct with high contact and severe impact and remained at the decision by the SANFL, despite the Power's Senior Counsel Kerry Clark attempting to use "exemplary disciplinary history".

Ms Clark illustrated that Dixon had never been previously suspended by the AFL or SANFL, while the 33-year-old gave evidence during the hearing.

Dixon stated that he had intended to tackle White, but after seeing the ball was disposed, he was attempting to turn away from the oncoming player to not give a free kick, rather than bump.

Ms Clark also noted that the amount of White is expected to miss due to concussion does not reflect 'significant' in the severe grading and therefore should be downgraded.

Despite the Tribunal accepting that Dixon's shoulder was below high contact, it still caused serious injury and that due to the concussion and the potential ramifications it has long-term, the suspension was upheld.

They also did not consider that exceptional and compelling circumstances of Dixon's exemplary record should apply in this case.

Dixon will be available again for selection ahead of Round 18 of AFL and Round 14 of SANFL.