Rugby's disciplinary system could be splintered by French authorities flouting Stade Francais hooker Laurent Sempere's suspension for eye-gouging, English administrators have warned.
Front-rower Sempere was handed a 15-week ban for gouging in Stade's 36-21 European Champions Cup victory over Leicester on January 24.
European Champions Cup bosses imposed the suspension, expecting the sanction to cover all competitions given rugby's universal application of disciplinary measures.
But France's rugby union and league chiefs granted an appeal by Stade Francais on February 22, allowing Sempere to resume action in the domestic Top 14 - almost 12 weeks before the end of his suspension.
Now bosses at England's Premiership Rugby are warning against a precedent that could radically alter the sport's disciplinary landscape, calling on global governing body World Rugby to intervene.
"If there isn't any action as a result of this directly, then the system is changed and we are in a completely different disciplinary environment," Phil Winstanley, rugby director at Premiership Rugby, told Press Association Sport.
"It creates some massive issues for us. Across any period of time you will always get a club, player or organisation who isn't happy with an outcome.
"But at least we have a system based on universality, that any sanctions apply across competitions.
"But now we've got a situation where that's no longer the case.
"Does it cause a problem for us? A massive problem."
Leicester face Stade Francais again in Sunday's Champions Cup quarter-final at Welford Road. Bosses at the Paris club did not appeal Sempere's ban to European chiefs European Professional Club Rugby (EPCR), and have not selected the hooker to face the Tigers.
Winstanley confirmed Premiership Rugby has made representations to the Rugby Football Union (RFU) on the matter. The English union has contacted World Rugby to express both their own and Premiership Rugby's concerns.
Sempere's ban was lifted in France by the February 22 hearing of the independent Extension Committee, a body set up in conjunction with French rugby authorities and World Rugby in 2009.
Lawyer Jean-Pierre Karaquillo chaired the hearing, with French Rugby Federation (FFR) and Ligue Nationale du Rugby (LNR) representatives also on the panel.
It is understood World Rugby consider this set-up to be unique in the sport, in part owing to the Code du Sport that is enshrined in French law.
While the game's global governing body is understood not to possess the jurisdiction to challenge the decision directly, a World Rugby spokesman said: "World Rugby is aware of the case and is in dialogue with EPCR and the FFR."
World Rugby is understood to believe the Sempere case does not threaten the principal of universal suspensions, but the global administrators are still making enquiries.
Premiership Rugby boss Winstanley remains at a loss as to how World Rugby had the power to intervene in the RFU and Six Nations' handling of England prop Joe Marler's "gypsy boy" slur against Wales' Samson Lee, but remain unable to act officially on Sempere.
"For World Rugby to be unable to get involved in the Sempere position and it to be out out of their jurisdiction, but yet they can call on a decision with Marler and the Six Nations, is absolutely ludicrous," said Winstanley.
"We're watching the current situation very closely and with interest, but we're not prepared to allow this to go away.
"What we're not prepared to accept and what we can't accept is an inconsistent application of a particular regulation which allows one player in one competition to be treated differently from the same player in a different competition."