Inter meet Red Star on Tuesday night on the back of victory over Udinese.
“As we’ve already seen in Europe in their matches against Bodo/Glimt and Benfica, Red Star are a team in good form,” said Inzaghi.
“In the league, out of nine matches they’ve had eight wins and one draw. So over the last day and a half we’ve tried to study them and prepare for them well. And then clearly as we know, all European matches are difficult.
“Tomorrow we’ll have to stay very switched-on.”
Inzaghi also said: “We’re used to having to play every three days. But that’s where we need to do well.
“We need to find the consistency that we’ve lacked so far. But we’re working hard so that it comes as soon as possible."
He said of their current form: “At the moment, whenever the opposition get into our penalty area, they seem to score a goal against us.
“We know that matches are tough in Italy, as they are in Europe. We have to keep our focus high and work as a team. As we have done in the last few years."