England rugby league captain Kevin Sinfield's cross-code switch could widen Scotland's rugby union World Cup options according to administrators in the 13-a-side game.

The 34-year-old generated a major shock this week by announcing that he is to join Yorkshire Carnegie, neighbours of Leeds Rhinos the club he has represented throughout a stellar career which has seen him become the fourth highest points scorer in rugby league history.

In doing so he joins former Scotland head coach Ian McGeechan, Carnegie's director of rugby and former Scotland captain Bryan Redpath, their head coach and it has emerged that Sinfield is qualified to join them in the Murrayfield role of honour.

"We know Kevin is Scottish qualified because his older brother Ian played for Scotland nine of 10 years ago," explained Gavin Willacy, Scotland rugby league's press officer.

"I think his qualification is on his mum's side. We never got within a million miles of getting Kevin to play for us, though. He was always destined to play for England."

At such an advanced age Sinfield faces a big enough challenge to adapt to the demands of the second tier of English rugby union, where Carnegie currently play, let alone facing the rigours of Test rugby, given the difficulty that Sam Burgess, his rugby league World Cup team-mate, has had since switching codes to join Bath.

However as well as being a points machine he is one of the most versatile performers in the sport having played stand-off, scrum-half, hooker and loose forward for his country as well as second row and centre for Leeds.

Given England's rugby union strength in depth there seems little chance of him being targeted by their coaching staff, however Scottish rugby is by no means over-loaded with play-makers.

"It will be interesting to see which position he plays in union but he is such a gifted player that he could make the adjustment quicker than most," said Willacy.