Lautaro Martinez ya taimakawa Inter Milan ta fara jagoranci ana fara wasa da taimakan Lukaku, yayin da kuma dan wasan ya kara zira wata kallon bayan wasu mintina.
Romelu Lukaku shima yayi nasarar cin kwallo guda a wasan inda suka lallasa AC Milan daci 3-0 kuma suka fara jagoranci da maki hudu a saman teburin gasar.
AC Milan 0-3 Inter Milan: Romelu Lukaku scores in derby as Serie A leaders go four points clear
Lautaro Martine gave Inter an early lead with header from Romelu Lukaku cross and then double advantage with tap-in at the end of team move.
Lukaku then put the nail in the coffin with a sensational solo run as he collected the ball in the centre circle and surged through the middle before beating Gianluigi Donnarumma at his near post.
The three points take Inter four points clear of AC Milan at the top of the league, one week after overtaking their city rivals who had been top since October.