The 23-year-old has not been shy of alcohol related issues in the past – he was banned for four games and ordered to undergo alcohol counselling after a naked, drunken rampage in the Cook Islands in November 2011 – and has now admitted his involvement in an incident that occurred after a private house party which is now being investigated by his team and the NZRU.

Guildford also had to apologise for his ‘excessive drinking’ and only narrowly escaped a playing ban at the 2011 World Cup.

He has voluntarily stood down from the franchise.

‘We and the Crusaders were very disappointed to learn of this incident. As a result, the NZRU has initiated misconduct proceedings against Zac,’ NZRU chief executive Steve Tew said in a statement.

‘We will be meeting with Zac and his representative in the following week to discuss the matter, and next steps,’ Tew added.