The Nerazzurri finished in ninth position under Andrea Stramaccioni, but the Brazilian hopes for better under new boss Walter Mazzarri.
"I confirm that it was a really difficult year for the whole team," he told reporters in his home country.
"Inter are used to fighting for the top positions.
"It was hard for us, but now we want to start over and do well next year.
"It's going to be an important season for us."