The organisers of the Rugby World Cup in New Zealand say counterfeit merchandise undermines the game and they will be taking a tough stance on people caught selling fake items.
Customs officers have intercepted a shipment of more than 1000 unlicensed Rugby World Cup t-shirts.
The consignment was detained by officials last month, and Customs says it would have been destined for discount shops, markets or for sale over the internet.
The general manager of Rugby World Cup New Zealand 2011, Ross Young, says exploitation by counterfeiters undermines the future growth of rugby as the sport relies on all revenue, not just gate sales.
Mr Young says official t-shirts are retailing for about $40 and buyers should examine the quality of products before purchasing.