"The heat is incredible. The other day I was feeling a bit dizzy and I had to sit down on the ground," Argentinian playmaker Fernandez told reporters on Friday.
Sunday's Club World Cup final at the MetLife Stadium just outside New York between Chelsea and PSG will kick off at 3:00 pm local time (1900 GMT). Temperatures then are forecast to be as high as 31 degrees Celsius (88 degrees fahrenheit).
Chelsea kicked off at the same time in their 2-0 semi-final win over Brazilian side Fluminense on Tuesday, and the heat has had an impact on numerous games throughout the competition.
That has led to concerns about scheduling during the World Cup set to take place across North America next year.
"Playing in these temperatures is very dangerous," said Fernandez, who was speaking before Chelsea trained at the Sports Illustrated Stadium in New Jersey, home of MLS side New York Red Bulls.
"Obviously for the spectacle, for people who come to the stadium to enjoy it, and for those watching at home, the pace of play is not the same, it slows everything down.
"Let's hope they change the kick-off times to make it a better spectacle," Fernandez, a World Cup winner with Argentina in 2022, added with an eye on the 2026 tournament.
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