The result saw Inter slip further behind the leaders.
“We will need many points this season and have to face games with the right mentality and belief, like we did today," said Spalletti.
“I expect what this team has already done during this first half of the season and I won't be influenced by the judgment of others."
Lazio coach Simone Inzaghi felt his team deserved the victory this evening.
“I could say the same, I could say different, it's up to everyone to have their own individual opinion. I am not interested in replying to what others say.
“What interests me is knowing the team put in a good performance. We were organised for this game and tonight I found all the ingredients in the right place."