Felipe Contepomi is set to miss out on all six of Leinster's pool matches in the Heineken Cup that begins next weekend following an administrative blunder.

The Argentinian outhalf, who signed a four-year deal for Leinster last May, while playing for Bristol, is expected to make his debut for the province in today's Celtic League match against the Celtic Warriors in Neath and a week later was expected take his place in the European Cup against Biarritz at Lansdowne Road.

The administrative faux pas came to light at a board meeting of the European Rugby Cup Ltd (ERC) yesterday, when Leinster proactively admitted their oversight.

It seems a breakdown in communication - or more accurately, a lack of specific dialogue - resulted in the misunderstanding that - unless Leinster advance beyond the pool stages - could preclude Contepomi from playing in the European Cup.

A form that includes boxes for date of birth, height and weight, among other things, also contains a box called the clearance/acceptance form.

This was ticked, as normal, in Contepomi's case but it must be backed up by release forms from his former employer (Bristol) and the union under whose jurisdiction he has been playing, the English Rugby Union (RFU). Those forms should have been submitted along with the other form containing squad information by November 13th.

Leinster assumed the IRFU were in possession of the release documents, but Irish rugby's governing body believed Leinster were in possession of the relevant forms.

The date passed and it was only last week that the error was noticed. The forms were duly lodged with ERC but by then the due date had passed.

In the past the IRFU has generally handled the registration of overseas players but the circumstances of Contepomi's arrival weren't as straightforward.

He was signed on May 19th after a covert approach to Bristol, who agreed the move. They were still involved with relegation issues and so the player returned to the club until May 31st, the end of their season.

With the exception of a trip to Dublin for a medical, Contepomi spent the summer with Argentina, first on tour and then at the World Cup.

The upshot of the administrative mix-up is that Contepomi, as things stand, is not eligible under the rules of the competition to play in any of Leinster's six pool matches.

The player was informed of the situation, along with his stunned team-mates, in Wales last night, where they were preparing for today's Celtic League match at the Gnoll.

Leinster have not yet abandoned hope of retrieving the situation and a  five-man management committee will review the situation on Monday.

A spokesperson for Leinster did last night confirm it was the province who had brought the error to the ERC's attention and that the province had not given up home of remedial action.

On the face of it, it is a cock-up of monumental proportions that such a prized asset, signed to a four-year contract, and welcomed in with a fair amount of fanfare, could be the victim of such an administrative howler.

On a practical level, Contepomi is still expected to start today's game but in the light of yesterday's developments, it means that - with a view to the Heineken Cup game against Biarritz this day week - Christian Warner may get more game time today than might otherwise have been expected.