Inter thumped Benevento 5-2 last week.
“No one expected to concede a goal after only a few seconds," Maggio told Radio Kiss Kiss Napoli. “The plan failed.
“Then I got injured. We will try to put the big teams in difficulty, but that evening everything went wrong.
“The most shocking thing is the bench. They have a great squad and one of the best managers around.
“They have young and experienced players, Inter can do well this year."