The Human Rights Tribunal of Ontario had proposed the mediation "to provide the parties with an opportunity to resolve the matter in a timely way." Adjudicator Jo-Anne Pickel made the offer Friday after turning down a request from a group of elite players for an expedited hearing on their legal challenge.
Pickel said in her interim decision that both the women and CSA had indicated in their filings that they would be willing to go to mediation.
A lawyer for the women quickly confirmed its willingness to take part in mediation. But the CSA, in keeping with FIFA's position that there is no Plan B to using artificial turf, subsequently declined.
The CSA did not deny its position had changed. Its position Friday was there is no need for mediation since the complaint itself has no merit.
"Either the tribunal was misled by CSA or it was mistaken in a fundamental way that clearly requires revisiting the players' request to expedite," Hampton Dellinger, lawyer for the players, said in statement Friday evening. "Whichever is the case, we will ask the tribunal to reconsider its decision not to hear the application on a fast-track basis.
"The tribunal's decision was based on a false assumption that CSA was willing to join the players at the negotiating table. Clearly that is not the case. A hearing on the merits is now more important than ever."
American star Abby Wambach and a group of other elite female players lodged their complaint Oct. 1, arguing that forcing them to play on artificial turf was discriminatory since men play their showcase event on natural grass.
The CSA rejects that claim, saying the world governing body of soccer sanctions playing on artificial turf as long as it meets certain standards. FIFA, meanwhile, has argued that artificial turf makes sense for Canada's climate while suggesting a men's World Cup could be played on approved turf "sooner rather than later."
In filing the turf complaint, lawyers for the players asked to fast-track proceedings so arguments could be heard by Nov. 26 in order to have enough time to install grass surfaces by the June 6 start of the 24-country tournament.
The CSA, which doubles as the tournament's national organizing committee, opposed the request. It argued both that the claim had no merit and the players had dragged their feet in filing it.
With no mediation and no fast-tracked hearing, the complaint will presumably wind its way through the human rights tribunal calendar. For the CSA and FIFA, no doubt out of sight is out of mind.
FIFA has not actively taken part in the legal proceedings.
In her interim decision on Wambach vs. Canadian Soccer Association, Pickel said there were factors on both sides of the argument, noting that the tournament is "fast approaching" and installation of natural grass would take time.
But "given the jurisdictional complexity of the case," Pickel said she doubted whether even an expedited hearing might result in a timely decision.
Pickel also agreed with the CSA that the players had not acted "expeditiously" in filing heir complaint, given that artificial turf had long been part of the tournament plans.
"It must be remembered that an expedited application is given priority for Tribunal resources over all other matters currently before the Tribunal," she wrote. "What the applicants are in effect requesting is that the Tribunal give their application priority over all the many other applications that have been filed with the Tribunal alleging violations of the (Human Rights) Code."
Earlier in the day, a group of 13 U.S. senators sent a letter to FIFA and U.S. Soccer in support of the female players.
Led by Sen. Sherrod Brown of Ohio, the lawmakers signed letters sent Friday to FIFA and the U.S. Soccer Federation in support of players who say that holding the World Cup on artificial turf amounts to gender discrimination because men play soccer's premier tournament on real grass.
The 12 Democrat and one Republican lawmakers urge soccer's international governing body to "reconsider this short-sighted and counterproductive decision."
"Currently ranked first in the world, the United States women's national soccer team has made our country proud time and time again," the letter addressed to FIFA president Sepp Blatter says. "As members of the United States Senate, we are deeply concerned with FIFA's treatment of these players. We urge you to begin good faith negotiations with these athletes, free of retaliation and with the equal treatment that they deserve."
With files from The Associated Press.
Follow @NeilMDavidson on Twitter.