Lazio has a mountain to climb if they want to walk out of the San Siro with at least a point.
Romelu Lukaku has scored his second goal against the Biancocelesti as Inter Milan now possess a 2-0 lead as the match heads into half-time.
The official initially marked the goal by Lukaku offside when the ball bounced off a Lazio player and landed at the feet of the Belgium international, who beat Pepe Reina.
However, after consulting with the video assistant referee (VAR), the call was reversed, and Inter took a 2-0 lead.