Fresh allegations from a drunken binge by All Blacks World Cup winger Zac Guildford have emerged involving a triathlete in the Cook Islands.

The original allegations ended with Guildford staggering naked and bleeding into a bar then assaulting two people but further details have emerged.

Kelly Pick, a triathlete in the small Pacific nation of the Cook Islands, said Guildford also repeatedly made lewd sexual comments and harassed her as she was on a training run along a road on the main island Rarotonga.

"His behaviour was totally inappropriate to the point where I felt unsafe," Pick wrote in a letter published in the Cook Islands News Tuesday.

"He was obviously highly intoxicated and driving his rental scooter very dangerously and speeding like an idiot.

"I got back from my run totally shaken and angry that someone feels they have the right to harass and leer at other people."

Pick told Radio New Zealand she had lodged a complaint with Cook Islands police about Guildford's behaviour last Thursday.

"(He) can't just continue this kind of behaviour and there be no consequences for him," she said.

Guildford issued an apology Monday over his conduct, saying he was "hugely embarrassed" and would seek help to "sort myself out".

The 22-year-old, who has a history of problems with alcohol, was publicly reprimanded by All Blacks management during the recent Rugby World Cup.

He reportedly appeared at a popular Rarotonga bar last Thursday night dripping wet, naked and bleeding from cuts believed to have come from a scooter accident earlier in the day.

The bar's owner, Jack Cooper, told Radio New Zealand Monday that the winger stumbled into the waterfront venue and hit two patrons, one of whom was celebrating his 60th birthday.