The Italians had to come from 2-0 down to claim victory and Prandelli was far from impressed with the performance .
Speaking to Rai Sport after the game, Prandelli said: "We deserved the win against Mexico, but struggled like crazy tonight. The humidity is something we have to deal with, as it really is difficult.
"We were 2-0 down and in the first 25 minutes didn't know what we were meant to be doing. We got it back on track and then tried to preserve the result because we had run out of gas!
"I need to get the team back and then I don't know what performance we can put in against Brazil. The humidity and heat is unbearable, so we have to figure out how to deal with it."
Italy play Brazil in Salvador on Sunday evening.