Troubled All Black wing Zac Guildford will take an indefinite break from the Crusaders as he seeks treatment for personal issues.

Guildford, 23, who has a history of alcohol and gambling-related problems, is facing misconduct proceedings after an off-field incident earlier this month when he reportedly became involved in a brawl with a man at a party.

The New Zealand Rugby Union said he had decided to withdraw indefinitely from the Crusaders ahead of the Super Rugby season to undergo an intensive treatment programme.

"Zac's withdrawal from the Crusaders means they are able to concentrate on preparing for their 2013 season, and Zac will be free from rugby to concentrate on resolving his personal issues," NZRU Chief Executive Steve Tew said in a statement.

Guildford admitted to having alcohol issues when publicly reprimanded by the All Blacks' management during the 2011 World Cup and two months later announced a 12-month drinking ban after he ran naked into a bar and allegedly punched two men.

New Zealand Rugby Players Association chief executive Rob Nichol said Guildford had accepted he faced a major challenge which meant he had to put his career on hold.

"We have taken the advice of experts and Zac is committed to the plan they have developed," he said.

"It is fundamental that he commits fully to the plan, and sees it through - this means withdrawing from the rugby environment.

"We are all supporting Zac during what will be a challenging time. Zac himself wants to make the most of the opportunity provided and is very appreciative of the support he is receiving."

Tew said it has been a "challenging week" for everyone involved.

"We are working closely with the Players' Association and his Manager to ensure that he gets the professional help he needs and is held accountable for his actions," Tew added.

"As people may appreciate, this is an employment matter and we must ensure that the process both respects his right to a fair hearing and our legal obligations as an employer.

"We also have a responsibility to the wider game and all those who support it. We are working hard to deliver on our obligations to the game.

"We will remain in touch with Zac to monitor his progress and will address the issue of misconduct at the appropriate time."

The Crusaders said they are unable to comment on the formal process currently being undertaken in relation to Guildford.

The process is currently with the NZRU, the Players Association and Guildford’s management team.

Crusaders Head Coach Todd Blackadder said: "We are all supporting Zac and see this as a positive step forward in overcoming his illness. This is ultimately about his well-being so it is important for him to take the time to fully address it.  

"We are unclear on what it means for the Crusaders at this time."

The wing has played 10 Tests and scored six tries for the All Blacks.