Romanian referee Vlad Iordachescu had to be led away from Spanish players who were furious with the way he officiated their 18-10 defeat last month, which seemed to have ended their hopes of qualifying for the tournament in Japan next year.
Rugby Europe last week delayed a decision on the contentious encounter after Romania and Belgium were accused of fielding ineligible players during the Rugby Europe Championship.
The world governing body initially came to the conclusion that the clash between Spain and Belgium should be replayed, but has now asked Independent Judicial Panel chairman Christopher Quinlan QC to form and convene a committee to conduct a review.
A World Rugby statement said: "World Rugby will convene an independent disputes committee to examine issues arising from the 2017 and 2018 Rugby Europe Championship, competitions that doubled as the European qualification process for Rugby World Cup 2019.
"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.
"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. Having considered all available information, the World Rugby Executive Committee and Rugby World Cup Board felt that a replay would be in the best interests of the game.
"Since expressing that view, new information relating to player eligibility in the Rugby Europe Championship has been presented to World Rugby by the participating unions. Given this information concerns potential breach of World Rugby regulations and given the complexity and interconnectivity of the issues, a full and independent review is warranted. This is in the best interests of the sport, teams and fans and is fully supported by Rugby Europe.
"World Rugby's independent Judicial Panel Chairman Christopher Quinlan QC has been asked to form and convene the disputes committee, as permitted under the Rugby World Cup 2019 qualification terms of participation, on an emergency basis in order to achieve certainty as soon as possible.
"A separate independent judicial panel has been appointed by Rugby Europe to consider conduct of the players after the final whistle of the Belgium versus Spain match."
Photo Getty Images. Caption: Spain players confront referee Vlad Iordachescu