Former Springbok halfback Kevin Putt, now a housemaster at King's College in Auckland, is adamant performance-enhancing drugs are being used in secondary schools rugby and welcomes the testing programme being introduced by Drug Free Sport NZ.
But he also warns there is a wider education process needed to teach players the pitfalls of steroid use.
"I think it's an immensely proactive stance," the former Waikato halfback and Counties Manukau coach told Radio Sport Breakfast. "This should be seen as a positive stance - it's one of actually trying to protect and look after the kids.
"We talk about 'oh my gosh, what are the consequences?', but hopefully it will come with a huge educational process."
Putt told RSB that many of his Kings players undergo that education as part of the NRL rugby league pathway.
"The earlier that happens, the better, because we all know that schools are now the catchment for rugby. You don't go to clubs any more to make it to the big time - they're actually picked up at school level, so there's more pressure on our young kids.
"I think the biggest concern is explaining the difference between supplements and performance-enhancing [substances] - one is a completely illegal drug.
"Some of the research done ... they did a survey of 12,000 boys and found that 10% have taken illegal steroids. That's not taking supplements - they're all taking supplements - but 10% are taking steroids."
But Putt admitted that even an education probably wouldn't change young players' attitudes towards drug use.
"Kids look at themselves, especially at our college, where they're a lot smaller than others, and think they have to get bigger to compete.
"You've got to hope they take a moral attitude, and that they're educated that they will still mature and that late maturers don't necessarily get missed in the whole programme. Let your skills do the talking."
Putt insisted supplementation was a separate issue and harder to stamp out in certain communities.
"Take South Auckland," he told RSB. "We already know schools are struggling to feed the kids coming through.
"Food first is fantastic for families that can afford it, but for some of these guys ... if they can get a milkshake with a heap of whey protein, that might be the best looking meal those kids are getting today.
"I think it's wrong speaking to people about supplements and performance enhancement. The suggestion is that supplements merely act as an early drug to lead you onto the bigger illegal drug scene - that is possible, but it may not be factual.
"What we're looking at here is performance enhancement - that is people trying to get an illegal method of getting bigger, stronger and faster.
"Does it happen? I'll guarantee it happens.
"Is it putting more pressure on young men and ladies in the system? I've got no doubts whatsoever."
DFSNZ will test schoolboy rugby players for the first time at the national first XV series at Palmerston North in September.