Former Warriors rugby league coach Matthew Elliott has revealed he always suspected players were abusing prescription drugs but lacked evidence to prove it.
Six Warriors players have been stood down from club and international duty after five of them admitted to mixing a cocktail of sleeping pills and energy drinks on a night out last week.
Among them is winger Manu Vatuvei who has since been on medical leave.
Elliott, who coached the Warriors for 18 months before being sacked in early 2014, told Fox Sports in Australia he suspected players were abusing prescription medication but had nothing he could take to the NRL to prove it.
"I suspected [prescription drug abuse]... the last person that knows in those circumstances [is the coach], because those prescription drugs aren't performance enhancers," Elliott said.
"They're the exact opposite, they're performance detractors - the head coach will be the last person to know. I suspected as much though."
"I also think it's an issue right across professional sport - we've seen it with swimmers and it's also an issue across our community," said Elliott.
"Players take the opportunity to use them for a number of reasons. Not only (to deal with) emotional issues, but to get themselves a little bit loose as well."