Welsh rugby chiefs last night pledged an immediate review of their top players' qualification credentials after claims that New Zealand-born forward Brett Sinkinson is ineligible to play for the country.

Neath flanker Sinkinson is at the centre of an allegation that he has no Welsh qualifications, despite claiming that his only British grandparent hails from Carmarthen.

On the strength of that background, he was selected to make his Wales debut against France a year ago, and has now won 14 caps.

Ironically, he has been ruled out of next Saturday's Six Nations Championship clash between Wales and Scotland, due to a rib injury sustained in a club match on Saturday. The allegations against Sinkinson, made in yesterday's Sunday Telegraph, have sent shock waves through the sport in Wales, and prompted a review ordered by Welsh Rugby Union secretary Dennis Gethin.

"Following stories in the media this weekend, questioning the eligibility of certain Welsh players, the WRU has decided to examine once again the credentials of all players who wish to play for Wales," said Wales team manager David Pickering.

"The WRU has always adhered to the International Rugby Board regulations regarding eligibility of players for international teams, and has taken in good faith the evidence and word of those players who wished to make themselves available to Wales via the parental and grandparental route."

The Sunday Telegraph claims that Sinkinson's British grandparent was a slaughterhouseman, born in Oldham. That would make the 29-year-old available for England, not Wales.

Wales coach Graham Henry, meanwhile, got on with the job of preparing his squad for Scotland's visit. The Welsh have been hit by injuries, so much so that today's planned team announcement could be postponed.

Outhalf Neil Jenkins, the highest point-scorer in international rugby history, is rated "very doubtful" because of a shoulder problem.

Lock Craig Quinnell's back injury also makes him extremely doubtful, skipper David Young is continuing his recovery from a back injury that forced him off against England eight days ago, while scrumhalf Rob Howley has a calf strain.

On top of that, neither centre Allan Bateman (dead leg), nor number eight, Scott Quinnell (neck) took any part in yesterday's closed training session.