Sonny Bill and Foran sleeping pill suspects

Sonny Bill Williams and Kieran Foran have been identified internally as two of several Kiwis players under investigation for allegedly taking sleeping pills and energy drinks at the 2013 Rugby League World Cup.

Sources within the team have said the experienced duo were two of the players singled out at a players-only meeting after the quarter-final against Scotland. There were at least five Kiwis players involved across the tournament and, in the meeting before the semifinal, some were "named and shamed" over use of sleeping pills and energy drinks and told it must stop. The Herald on Sunday is still confirming the identity of others.

Mixing sleeping pills with energy drinks is not illegal; the combination of the stimulant of the energy drinks and the sleeping pills can produce a sensation not unlike recreational drugs but does not fall foul of drug laws.

The Herald on Sunday reported last month that during the World Cup there were concerns about some individuals, with players confronted because of their appearance and asked if they had been drinking; some players looked 'dozy and half asleep' at the wrong time of the day.

Williams and Foran, who both played in the NRL 2013 Grand Final, were room-mates for part of the World Cup. They have been mainstays of the Kiwis and play with great heart - Williams was clearly the best player in the semifinal. Both are model trainers and Foran was outstanding when given the captain's armband at short notice in last year's Anzac test.

The circumstances of the tour are part of an ongoing review by the New Zealand Rugby League.

NZRL CEO Phil Holden, when asked about the identity of the players, said: "We are not going to be confirming or naming players. There is nothing to be gained and we can't. I have made it very clear that this is not a linear issue; it is very complex, privacy laws are involved, employment laws and contractual obligations between us, the players and the organisation."

"At the heart of it, it is not illegal and that makes it really difficult moving forward from there," added Holden. "When we get down to it, we are looking at what we can do around education, what we can do in terms of their contracts with us, what we can do in terms of testing for example, what we can do in terms of their obligations to us and reinforcing our code of conduct. It is not just a rugby league issue ... it is a societal challenge in many forms.

"We are the focal point right now but I am conscious it is a broader issue."

The NZRL has been in discussion with Drug Free Sport New Zealand to see what testing options are available in the future and have been working closely with the NRL.

"The NRL has been positive," says Holden. "They are looking at establishing a taskforce to look at their own policies and processes in this space so I think that is a positive outcome. We can't do much without their support [and] it might be included in an NRL code of conduct."

There are urine tests available to test for the presence of sleeping pills in the system but time is needed to process results, meaning detection would normally occur after the fact.

"I didn't think [rugby league] players were that dumb," said former Kiwis coach Graham Lowe in regard to the pills inquiry. "It can't be excused - it has brought the game into disrepute and didn't represent the Kiwis image that I knew. They [any players who have transgressed with sleeping pills and energy drinks] should have the book thrown at them.

"There can be no excuses. It brings everything undone; you can't afford to compromise the high standards, integrity and respect of the game."

Williams' manager Khoder Nasser and Kieran Foran did not respond to interview requests.