Inter were arguably the better team in an otherwise lacklustre first half in the 'Derby della Madonnina' but it burst to life in the 38th minute.
Icardi got on the end of a defence splitting pass before comfortably slotting it through Gianluigi Donnarumma's legs to take the lead.
However, following some deliberation, VAR decided to rule out the goal after images showed that the Argentine striker went a fraction early it what was a close call from the officials.
Check out the goal and annullment for yourself:
April 4, 2018