The Nerazzurri drew 3-3 with Parma in their Serie A match on Sunday evening and have now failed to win their last three games in the league.
"I believe many of these players are not accustomed to being first choice at Inter and they have started to feel the responsibility of that," he told La Gazzetta dello Sport. "These players are not used to having the pressure of being expected to win every time."
"We had a terrible start against Parma and we took 15 minutes to wake up. We must reflect on how we deal with certain moments of a match, as we often go too deep when taking the lead and end up conceding a goal.
"We dropped two points against Sampdoria, while against Parma, it was a balanced match and anything could have happened. We could easily have lost. We deserved more in other games, but probably not in this one."
Inter are currently fourth in the Serie A table.