The Granata went down to a surprise defeat against the relegation strugglers at the Stadio Bentegodi.
“We started badly, we knew what type of match it would be," a disappointed Mazzarri admitted after seeing his side beaten by Mattia Valoti's brace.
“We gifted them half of the match, in the second half we came out well. But after the equaliser we conceded the goal through our own mess."
After two defeats in as many matches, Mazzarri was asked whether his side struggle to react well to going behind.
“The derby is a particular match, we didn't do much in the match against Juventus.
“But today was different. We gave up a half, but in the second half there was a reaction.
“The balance was there in the second half, but if you make simple errors you lose.
“We were punished for switching off."