AC Milan boss Max Allegri insists the return to form of Inter was expected.
Milan have seen Inter haul in their points gap since Leonardo's appointment on Christmas Eve.
Allegri said: "The season is long. There are still many games left. I have never seen a team win the League in Italy with two months to spare.
"We knew that Inter would return to fight for the Scudetto. Napoli are having a great season and Roma are in the fight.
"The thing that we have to do now is stay concentrated."
Asked if he feels Zlatan Ibrahimovic and Alexandre Pato are compatible, Allegri said: "They only have to play together more and get to know each other better."
