World Rugby are to set up a disputes committee to examine Spain's controversial defeat by Belgium last month, as it revealed it was "deeply concerned" by events at the World Cup qualifier.
Victory for Spain would have given them an automatic place at next year's World Cup in Japan but they suffered an upset 18-10 defeat by Belgium in Brussels in a Rugby Europe Championship match that also doubled as a qualifier for the global showpiece event.
Prior to the match, Spain had objected to the appointment of an all Romanian match officiating team as they knew that their defeat would send Romania directly to Japan 2019 instead.
At the final whistle referee Vlad Iordachescu was surrounded by outraged Spanish players.
Concerns were also raised by the fact Octavian Morariu, the president of Rugby Europe -- the organisation that oversaw the appointment of the match officials and rejected Spain's plea for a different referee and touch judges -- is himself Romanian.
"World Rugby was deeply concerned about the circumstances surrounding the Belgium versus Spain Rugby Europe Championship match, a match that was decisive in the context of Rugby World Cup 2019 qualification," said a statement issued from its Dublin headquarters.
"Specifically, concerns related to the process and perception of Rugby Europe's appointment of a match official team that was not neutral in the context of qualification and failing to act on Spain's concerns in respect of the appointment.
"While recognising Rugby Europe's responsibility to review events in their own competition, given the context and significance of the fixture World Rugby acted immediately to request information relating to the above issues from Rugby Europe and participating unions."
But amid calls for the match to be replayed -- which would be a huge step for World Rugby and set a precedent with worrying ramifications for a sport that sets great store by respect for match officials -- doubts have been expressed over whether all the Spain players who took part were eligible to represent the country.
"Given this information concerns potential breaches of World Rugby regulations, and given the complexity and interconnectivity of the issues, a full and independent review is warranted," the statement added.
"This is in the best interests of the sport, teams and fans and is fully supported by Rugby Europe."
World Rugby said judicial panel chairman, Christopher Quinlan, a leading London-based lawyer, had been asked to convene a dispute committee in order to "achieve certainty as soon as possible" regarding qualification for the World Cup.
Spain, citing 19 decisions they said went against them, had urged Rugby Europe to order a replay. But a meeting the continental body said it would call to look into the issue was postponed three times inside a week.
Thursday's statement added Rugby Europe had appointed a separate panel to consider the conduct of players following the final whistle when angry members of the Spain team confronted Iordachescu.