Selby-Rickit, son of former All Black Hud Rickit, has since acknowledged his behaviour did not meet the standard required of a professional rugby player.
New Zealand Rugby Head of Professional Rugby Chris Lendrum said the new Highlander signing would not be available for two of the Highlanders' two pre-season fixtures, or the first two Investec Super Rugby games of 2020.
He will be permitted to train with the team.
"We have made it clear that there is no place in rugby for violence and we expect better decisions from players when it comes to alcohol. Manaaki has been formally sanctioned with a warning, and we are requiring him to undergo counselling," the statement read.
New Zealand Rugby, the Highlanders and Selby-Rickit have also agreed a programme of counselling and monitoring to ensure he is committed to rehabilitation.
The Highlanders kick off thier 2020 Super Rugby season against the Sharks on February 7 in Dunedin.