KNOXVILLE — Researchers from the University of Tennessee at Knoxville and Michigan State University completed a five-year study on turfgrass for the FIFA World Cup 2026 fields. All 16 stadiums designated for the tournament currently meet FIFA's performance standards for ball bounce and traction.

John Sorochan, who leads the turfgrass science and management program at the University of Tennessee at Knoxville, collaborated with Alan Ferguson, FIFA's senior pitch management manager, on the project. The collaboration began eight years prior to 2026, when Ferguson approached Sorochan about World Cup field research during a meeting in East London. "When we first got asked, when Alan [Ferguson] asked me over a cup of tea and biscuits in an East London café eight years ago, we didn't know which stadiums were going to be hosting it," Sorochan said. "I asked, 'Will there be any indoor stadiums?' And he goes, 'I can almost assure there'll be one or two indoor stadiums.'"

The research addressed geographic conditions across Canada, Mexico, and the United States, which will host the World Cup. "The challenge was how do we make the different grasses, play, perform and be as similar as possible for the World Cup, knowing that Miami's going to be Bermuda grass and Boston's going to be a blue rye mix of cool-season grasses," Sorochan said. The team investigated construction methods for converting indoor and synthetic turf stadiums to natural grass surfaces.

A focus of the research involved stadiums with concrete floors, such as those in Dallas and Houston. The team explored methods for building above these concrete surfaces to create a playable soccer pitch. In contrast, stadiums in Philadelphia and Kansas City feature 12 inches of sand beneath their playing surfaces. Sorochan previously worked on the 1994 World Cup field at the Silverdome in Detroit, where grass was installed indoors for 30 days without grow lights, vacuum ventilation, or natural sunlight. "That's what inspired me to want to do research and grow grass indoors, which is what I'm doing today," Sorochan said.

The researchers conducted approximately 30 to 40 projects. A primary benchmark was the FIFA standard for soccer ball bounce, which requires a ball dropped from two meters to bounce between 60 centimeters and one meter. "We learned that if you have a minimum of three inches of sand and a drainage layer, you can't pick up the feel of the concrete below that surface," Sorochan said. He confirmed that all 16 World Cup stadiums are constructed according to FIFA requirements and pass the necessary protocols for ball bounce and traction.