The Ospreys await their Heineken Cup fate after Leicester Tigers made a complaint as the Ospreys played with 16 men for part of their 17-12 triumph.
The Welsh region knocked Leicester out as they qualified for the quarter-finals with their Liberty Stadium win.
The confusion was in the final quarter when full-back Lee Byrne returned from the blood-bin and his replacement Sonny Parker stayed on for a brief period.
The Ospreys are likely to be hit with a fine rather than European expulsion.
Tournament organisers European Rugby Cup will investigate the events in Swansea after Tigers chief executive Peter Wheeler and chairman Peter Tom lodged an official complaint immediately after the dramatic showdown.
Competition rules suggest the match result must stand, yet the Ospreys still face an anxious wait to discover what punishment – if any – ERC decides to impose.
England were fined £10,000 during the 2003 World Cup when wing Dan Luger featured as a 16th player for 34 seconds of their group-stage win against Samoa in Melbourne.
Unlike in Luger’s case, it is claimed on this occasion that Ospreys’ Wales and British Lions full-back Lee Byrne was involved in helping to thwart an opposition attack.

Byrne had gone off suffering from a dislocated and bloodied toe, being replaced by centre Sonny Parker, but Byrne was sent back on three minutes later without any of his team-mates going off.
Fly-half Dan Biggar’s departed in the 73rd minute after about a minute returned the Welsh region to 15 men as the Ospreys held on during a torrid finale of constant Leicester pressure.
A Leicester player pointed out the Ospreys’ numerical advantage to referee Alan Lewis, who then berated an Ospreys touchline official for not informing the match fourth official that Byrne had returned.
Lewis should have awarded Leicester a penalty once the extra-man situation became apparent.
Leicester chief executive Peter Wheeler said: “During a significant part of the game, the Ospreys had 16 players on the pitch, and he was involved in a break by Ben Youngs being stopped from developing.
“We think the interference of the 16th man was significant – you are only entitled to have 15 players on the pitch.
“We think it affected the outcome of the game. The players put their heart and soul into it out there, and they deserve to be treated fairly.”
Tigers chairman Peter Tom added: “A serious error has been made. We are 12 years or so into the professional game, and it is time administrative procedures were sorted out.
“There has been a significant mistake that could be said to have had an impact on the game.
“People who administer the game have to make sure it doesn’t happen again.”
Referee Alan Lewis gave a dressing down to an Ospreys official over the incident, telling her she should have told the game’s fourth official Byrne was returning to the field.
Byrne could be seen signalling to a team-mate he should depart, but did not leave the field when his message did not get through.

International Rugby Board rules state: “At any time before or during a match a team may make an objection to the referee about the number of players in their opponents’ team.
“As soon as the referee knows that a team has too many players, the referee must order the captain of that team to reduce the number appropriately.
“The score at the time of the objection remains unaltered.
“Sanction: Penalty at the place where the game would restart.”
No penalty was awarded by Lewis and the IRB regulation suggests the result will stand. However, ERC officials are duty-bound to investigate.
Leicester coach Richard Cockerill said: “I am sure they (Ospreys) didn’t do it purposely. I don’t think it had a bearing on the result.
“We were beaten fair and square. I am a lover of the game, and I am sure it was a mistake by somebody.”
Ospreys boss Scott Johnson said: “This is one for the officials. They can work it out.

“There was a call for Lee Byrne to come on and ‘X’ to come off – that was the instruction.
“Byrne came off as a blood bin, and maybe that’s where the confusion was. You just give instructions as a coach.”
And in a brief statement, the Ospreys said: “We are aware that a complaint has been lodged with ERC by Leicester Tigers.
“The matter is now in the hands of the ERC, and as such, it would be inappropriate for us to make any further comment on this issue.”
An ERC spokeswoman confirmed to BBC Sport that the ERC are “looking at the case” and will make a statement on Sunday.

The Ospreys have appointed former Wales fitness coach Andrew Hore as their elite performance director.
 
New Zealander Hore seemed to be on the verge of taking up the same post with the Wales national team in October.

But that apparently cooled last month when the Welsh Rugby Union announced they now had a three-man shortlist.

Ospreys managing director Mike Cuddy said the appointment is “an enormous statement of intent” of achieving success for the region.

Hore will take up his three-and-a-half year post in February after agreeing to step down as player development manager for the New Zealand RFU.

 He will be working closely with director of rugby Kevin Hopkins, head coach Lyn Jones and his coaching team, but will not be involved with on-the field coaching.

“The Ospreys are one of the most forward thinking and ambitious outfits in the northern hemisphere game and the opportunity to help them achieve their long term aims was too good to turn down,” said Hore.

“It was a difficult decision to step down from my role with the NZ RFU but the challenge presented to me by the Ospreys is as exciting a challenge as there is in world rugby.

“I know the area and many of the personnel at the region very well from my previous stint in Wales and that’s certainly helped with my decision.”

Hore has worked in Wales before – having previously held the post of fitness coach at the WRU between 2002 and 2005 – working alongside coaches Steve Hansen, Scott Johnson and Mike Ruddock.
 
Cuddy added: “I think that the appointment of an individual of such stature throughout the world of rugby is an enormous statement of intent from the Ospreys.

“It is a clear demonstration of our intention to ensure the Ospreys a place at the top table of European rugby, not just today but in the long term.

“The Ospreys have now been operating for four-and-a-half years, and over this time we have undoubtedly gone from strength to strength, but we felt that the time was right to look to strengthen the rugby side of our business even further.

“In Andrew, we have one of the most respected young rugby brains in the world, and he comes with a proven track record.

“He is right at the cutting edge of rugby thinking and will bring to the table a different outlook on how to do things with his experience of the domestic game in New Zealand and the international game, and this knowledge is something that we don’t have at the moment.

“We want to be considered one of the top five teams in Europe, to be mentioned alongside the likes of Wasps, Leicester, Toulouse and Stade Francais when people talk about potential European Cup winners.”

The WRU has welcomed Hore’s appointment at the Ospreys, describing it as a “bold step” which will “enrich the player talent base across Welsh rugby”.

“We spoke at length with Andrew about the possibility of him joining the WRU but it didn’t work out, for all the right reasons,” said WRU group chief executive Roger Lewis.

“That’s why we are so delighted he is still coming to Wales to work with one of our finest regions.”

Three Welsh rugby players, including international centre Gavin Henson, are facing court over separate allegations.

Henson, 25, has been summonsed to appear before Cardiff magistrates accused of disorderly conduct.

The Ospreys centre and three friends will be prosecuted over allegations of drunken antics on a train from London to Cardiff eight days ago.

Meanwhile Newport Gwent Dragons players Rhys Thomas, the Wales prop, and Rhodri Gomer-Davies, are in jail in Italy.

The allegations against Henson and three friends relate to Sunday, 2 December, when he was returning from a game which saw the Ospreys beat Harlequins.

The other men facing prosecution are Jamie Mark Griffiths, 26, David Norman, 33, both from Bridgend, and Matthew Rhys Williams, 25, from Wick, Vale of Glamorgan.

In a statement, British Transport Police (BTP) said: “Four men are to be prosecuted for public order offences following a disturbance on the 1937 First Great Western London Paddington to Cardiff train on the evening of Sunday, 2 December.

“At 9.25pm on 2 December, BTP officers at Cardiff Central responded to a call to a group of men causing a disturbance on the train.”

BTP said the men were being summonsed to Cardiff Magistrates’ Court for offences contrary to Section 5 of the Public Order Act 1986.

No court date has been set, but it is likely to be in January.

Henson, from St Brides Major, Vale of Glamorgan and his friends were questioned by British Transport Police (BTP) when the train arrived in Cardiff.

Henson’s partner, singer and TV presenter Charlotte Church, had their first child, Ruby, in September.

Meanwhile, in the separate case, it is understood that Newport Gwent Dragons players Rhys Thomas, 25, and Rhodri Gomer-Davies, 24, will appear in court in the Italian city of Treviso on Monday morning.

They were held after a fracas outside a nightclub in the city after their club’s Heineken Cup victory over Treviso.

The regional side has confirmed two of its players broke a team curfew on Saturday night after the 35-33 win.

Wales fly-half James Hook has re-signed for Ospreys in a deal which will keep him with the region until 2011.

Hook, 22, has won 15 caps for Wales and will be a key player during the upcoming World Cup in France.
 
“I am delighted to have re-signed with the Ospreys,” said Hook, who scored Wales’ try in their 34-7 defeat to France last weekend.

“This region is going to have massive success over the next few years and I want to be a part of it.

“I have grown up in the area, the Ospreys are my local professional side and I just could not imagine going anywhere else.

“We have facilities and a growing fan base that will rival any European side and this makes it a great time to be a player at this region.”

Ospreys director of rugby Kevin Hopkins added: “We are delighted to have secured another of our young key players on a long-term contract.

“James is a player of massive potential and this is becoming more and more evident with each match he plays for Wales and the Ospreys.

“It is great news for both Wales and our region that he is staying with the Ospreys.

“This is another key step towards us achieving our ambitions, both domestically and in cross-border competitions over the coming seasons.”