Highlanders and All Black loose forward Shannon Frizell is alleged to have assaulted a woman at a Dunedin bar at the weekend.
Senior Sergeant Craig Dinnissen earlier said a rugby player "of significance" was involved in an incident at Vault 21 around 2.30am on Sunday, and police later confirmed they were investigating an incident at an Octagon bar.
Police were notified of the allegations on Sunday. Officers did not attend the incident.
Nobody has been arrested.
Highlanders chief executive Roger Clark was aware of the incident.