World Cup officials this week announced they were to begin testing for the new ’designer drug’ tetrahydrogestrinone (THG) at the beginning of next week, a move that has received unanimous backing from coaches.

Kirwan believes rugby, with its relatively clean reputation, has a responsibility to lead the way in drugs testing and must be ruthless in stamping out cheats.

“I love the sport of rugby, it has given me so much. If anyone is cheating they should be stopped and banned forever,” he said.

“I hope they catch all the cheats. It’s a great sport for youngsters and it’s very important we should lead the way as far as sports are concerned.

“Do as many tests as you like. All our guys gave been tested and I wouldn’t be very tolerant of someone that had cheated.

“Cycling is sad – I used to watch the Tour de France but now I just watch it at a glance because I think ’who is really winning this?’

“I would hate to see rugby get like that. So let’s do all the tests and whoever is cheating, let’s get rid of them.”

Kirwan revealed he harboured suspicions about certain individuals many years ago, but maintained rugby is a relatively clean sport.

“I played rugby for 20 years and saw occasions where it might have been used,” he said.

“I’ve seen it in the early days when no-one knew what it (steroids) was. I don’t think we can be naïve to say that out of all the rugby people, someone isn’t trying to have some performance enhancement.

“I think we need to clamp down hard on people who are using it and rugby needs to be a shining light in that area.”