TORONTO - Players on the U.S. men's soccer team have thrown their support behind the women fighting against artificial turf at the 2015 Women's World Cup.

The U.S. National Soccer Team Players Association issued a statement Monday saying its members "fully support the women's national team players from around the world in their efforts to play on natural grass at the 2015 Women's World Cup."

"We know firsthand the importance of playing the World Cup on natural grass and the ways playing on artificial turf changes the game's fundamentals." the statement said. "We have all played on artificial turf and we know there are circumstances where it is appropriate or conditions require its use, but the World Cup is not one of those circumstances.

"To play the Women's World Cup on artificial turf would be a serious mistake."

The association represents the U.S. men's national team players on compensation, working conditions and other matters. It also is the membership organization for alumni members of the U.S. men's team.

It has no link to the American women's team.

A group of elite female players from around the world has launched a legal challenge to the use of turf with the Human Rights Tribunal of Ontario, arguing that it discriminates against women because the men do not play their showcase tournament on artificial surfaces.

U.S. star Abby Wambach is one of several American women behind the challenge.

FIFA and the Canadian Soccer Association have dismissed the claim, saying the laws of the game allow playing on turf as long as it is of a certain quality.

"It's not as much about the legal challenge. It's about the importance of the World Cup and the Women's World Cup is a World Cup," Mark Levinstein, acting executive director and general counsel of the U.S. National Soccer Team Players Association, said in an interview. "And we think it's important that whoever's playing in a World Cup, that the World Cup is treated with a certain amount of respect."

That the U.S. men support playing on natural grass is not a surprise. But by doing so formally, they have injected themselves into the debate.

There is much for the men at stake in this debate too, with FIFA secretary-general Jerome Valcke saying recently that a men's World Cup could be held on artificial surfaces "sooner rather than later."

The statement from the U.S. men's team players gives the women another weapon in their arsenal, not to mention another headline. Both sides have taken turns firing salvos in the war of words, with FIFA using its website to strategically release information on its side of the argument.

The association representing the U.S. men's team players also weighed in on allegations that FIFA and national associations have pressured women not to join the legal challenge.

"We support the right of the women players to stand up for what they believe," said the association. "No player should ever be threatened with exclusion from their national team, damage to their career, or adverse consequences to their national team or the sport in their country (such as exclusion from the World Cup or damaging their country's chances of hosting a World Cup) for exercising their legal rights, especially when they are trying to protect the sport, the fans, and their fellow players.

"The message is simple and unequivocal: the World Cup should not be played on artificial turf and the organizers and the players should work together to schedule the games on grass for the benefit of the sport, the players, and the fans who will be attending and watching this and future Women's World Cups."

There seems no immediate solution, with the Canadian Soccer Association rejecting an offer of early mediation from the Human Rights Tribunal of Canada.

The CSA's position is because the players' claim has no validity, there is need to negotiate. And with the tournament starting in June, time is trickling away although the women say a solution — temporary grass surfaces or use of venues with real grass — could happen on relatively short notice.

The Human Rights Tribunal rejected the players' bid for an expedited hearing, offering up the early mediation instead and has several other matters on the issue to resolve before a full hearing can take place.

The Canadian tournament runs June 6 to July 5 in Moncton, Ottawa, Montreal, Winnipeg, Edmonton and Vancouver.

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