FIFA will only allow natural grass fields at the 2023 Women's World Cup.

The stipulation is contained in requirements sent to bidding nations and follows controversy over the use of artificial turf at the 2015 tournament in Canada.

Some players launched a gender discrimination case —which was later withdrawn — over FIFA's use of turf four years ago because men's World Cup games have always been on grass. They claimed the artificial surface is less forgiving than grass and impacts the game because of concerns over injury. They also claimed balls travel and bounce differently on artificial turf. FIFA said it wanted the same surface in every stadium.

FILE - In this Feb. 27, 2019, file photo, FIFA President Gianni Infantino holds the official ball of the upcoming Women’s Soccer World Championship as he poses for photographers during a press conference at the end of an executive committee meeting in Rome. FIFA's financial results underscore the glaring disparity between men and women’s soccer. “We need to try to find what is the most balanced way and I think we made a step and there will be many more steps going ahead,” Infantino said in October before his ruling council approved the 2019 Women’s World Cup prize scale. (AP PhotoGregorio Borgia, File)

FILE - In this Feb. 27, 2019, file photo, FIFA President Gianni Infantino holds the official ball of the upcoming Women’s Soccer World Championship as he poses for photographers during a press conference at the end of an executive committee meeting in Rome. FIFA's financial results underscore the glaring disparity between men and women’s soccer. “We need to try to find what is the most balanced way and I think we made a step and there will be many more steps going ahead,” Infantino said in October before his ruling council approved the 2019 Women’s World Cup prize scale. (AP PhotoGregorio Borgia, File)

This year's 24-team tournament in France will be played on grass in nine venues. FIFA has made it clear artificial surfaces won't be acceptable in 2023, either. What is permitted is the hybrid system used at many leading stadiums where millions of synthetic grass fibers are woven in between and beneath the natural grass.

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