Fox Sports, on its game broadcast, reported temperatures at turf level had reached 54 degrees Celsius during the early afternoon Norway-Thailand match Sunday in Ottawa and 43 degrees for the Germany-Ivory Coast match that followed.
FIFA listed the air temperature at 18 and 25 degrees, respectively, for the Ottawa doubleheader.
A Fox sideline reporter said turf temperatures had reached 49 degrees in Edmonton for the Canada-China game Saturday. Air temperature was 26 degrees.
The Canada and China coaches both referred to the heat in their post-game comments but did not point a finger at the artificial turf.
"I think that was the one thing (Saturday) that anyone watching at home probably didn't appreciate — the temperature on the field was very hot," Canadian coach John Herdman said Sunday.
The Canadian team spent a week in Mexico prior to the tournament to get acclimated to heat.
"We knew we could have some hot days (at the tournament) and we certainly got one," said Herdman. "And it slows the game down."
Herdman said his data showed the team would hit a plateau and then spike in energy. It didn't help that the Chinese lay back in defence, forcing the Canadians to expend more energy on attack.
He said that took its toll on his players at times but was pleased with the high-tempo finish from the Canadians.
Saturday's Canada kickoff was 4 p.m. local time. It should be cooler Thursday when Canada's game against New Zealand is a 7 p.m. start.
Defender Kadeisha Buchanan said while Saturday was hot, the Canadians had prepared for it in advance of the tournament. They had spent a week in Mexico to get acclimated to the heat.
"I didn't find it scorching hot. I didn't find it too too hot, like not (able) to function" she said of the China game. "But definitely there was a bit of heat."
Asked about the pitch-level conditions, a FIFA spokesman said its medical team is "always monitoring carefully all venues during any FIFA competition to protect the player's health."
The spokesman said key criteria for the medical team are based on the Wet Bulb Globe Temperature (WBGT) which is a composite temperature used to estimate the effect of temperature, humidity, wind speed (wind chill) and solar radiation on people.
The index was first developed by the U.S. military to help combat heat illness.
NOTES: Referee Michelle Pye of Kamloops, B.C, will serve as the fourth official at Tuesday's game in Moncton between France and England. Suzanne Morisset of Beauport, Que., will serve as reserve assistant referee for that match and the Colombia-Mexico game that follows.
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