That result leaves Inter sitting at the top of Serie A with 12 points from their opening four matches.

AC Milan are third with nine points.

Juventus, who beat Lazio earlier today, are second with 10.

What a result for Inter.

They have won five Milan Derbies in a row for the first time in the fixture's history and Simone Inzaghi's men continue their perfect start to the Serie A season.

AC Milan fought well at times but ultimately couldn't match their rivals' level.

Inter will record their biggest Serie A home win over AC Milan since a 4-0 win in April 1967.

Five minutes are added on at the end of the second half.

Despite their lead Inter have had just 39% of the ball in this game. They've been at their best on the break.

Ruben Loftus-Cheek goes off for AC Milan. Yunus Musah takes his place.

AC Milan look dejected now.

Even with a three-goal advantage Inter aren't letting up in their attacking pressure.

Hakan Calhanoglu's evening is over, however, and he is replaced by Kristjan Asllani.

Lautaro Martinez is fouled in the box by Theo Hernandez and Inter have a chance to score a fourth!

Now AC Milan look to the bench.

Luka Jovic and Noah Okafor come onto the pitch.

Olivier Giroud and Tijani Reijnders make way.

Inter make another change with Stefan de Vrij replacing Alessandro Bastoni.

Inter are on a roll now and go forward through Carlos Augusto. They are moving at breakneck speed on the transition.

AC Milan are struggling to ignite any sort of comeback since Leao's goal. Inter are well-composed, have dropped deeper once again, and the space just isn't there for AC to pose any threat.

Inter turn to the bench with Nicolo Barella, Feferico Demarco and Marcus Thuram making way for Davide Frattesi, Carlos Augusto and Marko Arnautovic.

Theo Hernandez goes into the referee's book after mistiming a tackle on Henrikh Mkhitaryan.

The rain at San Siro is nothing short of torrential and the ball is now skidding across the pitch.

That's the first goal Inter have conceded this season.