Italy coach Cesare Prandelli said experience gained from the Confederations Cup last summer and a subsequent strict focus on their physical condition paid dividends for his side in a win against England in Manaus.
He felt his side's superior condition was the main difference between the two sides as Italy ran out 2-1 winners at the Arena Amazonia, where the high levels of humidity still posed his side a problem.
Prandelli also criticised FIFA for denying teams timeouts for the heat.
"We were suffering and it's crazy not to have timeouts, so I had to tell my team to drop our rhythm instead," Prandelli told RAI television. "We suffered, but we had to try to do more than our opponents, particularly in midfield, where I wanted an extra man, and it worked.
"We worked very hard at [the Italian national training centre] Coverciano and you could see the difference it made -- they were getting cramps in the second half and we weren't, we were in better shape."
Mario Balotelli's headed goal was the difference between the two sides, and for a player who rarely celebrates when he scores, there was a slightly wider grin than usual on the AC Milan forward's face.
"I'm really delighted -- it's a unique feeling," he said to RAI. "I've never played in the World Cup before, and then for this to happen -- it's amazing. I want to dedicate it to my future wife, my family and to my friends at home who are certainly watching."
It was far from easy for Italy, though, and Balotelli admitted he was glad to put the heat and humidity of the Amazon rainforest behind him.
"The conditions really are extreme here in Manaus," he added. "It was terribly hot. Recife and the other places are also hot, but not like this. This was a very difficult game, but Italy always suffer -- it's one of our characteristics, but all that matters is winning, and this win will do us good."