Inter Milan scored two early goals to secure an impressive 2-0 win over AC Milan in the Champions League semi-final first leg on Wednesday and stay on course to become the first Italian team to win the trophy since they did so in 2010.
Inter struck after eight and 11 minutes, with Edin Dzeko smashing in a close-range volley before Henrikh Mkhitaryan doubled the lead from Federico Dimarco's cross to stun their city rivals at the San Siro.
Milan were shell-shocked and although they improved in the second half, they rarely threatened a comeback and face an uphill task to stay on course to win their eighth European Cup.
"Right from the first minute we had a great desire to win," player of the match Mkhitaryan told Prime Video. "But it's not over yet. A great battle awaits us."
Bosnian striker Dzeko, 37, became the second oldest player to score in a Champions League semi-final after Manchester United's Ryan Giggs. He struck twice in Inter's 6-0 win at Verona this month to end a near four-month goal drought.
"Sometimes you get in this difficult moment where the ball doesn't want to go in. Patience and work always pays off. I was calm knowing the goals would come as always," Dzeko said.
Three-times European champions Inter made a fast start when Hakan Calhanoglu delivered a corner which fell to Dzeko and the veteran Bosnian striker expertly fired the ball into the top right corner.
Inter, who came into the fixture in high spirits after four consecutive Serie A wins, doubled the lead through Mkhitaryan after Dimarco served him with a brilliant pass and the Armenian broke into Milan's box to find the net from close range.
Powerful shot
Calhanoglu went close to adding the third when his powerful long-range shot hit the inside of the post and Mkhitaryan was denied by Milan keeper Mike Maignan.
Milan, without injured forward Rafael Leao, were stunned and things could have got worse for the hosts when Lautaro Martinez went down inside the box just after the half-hour mark.
The referee pointed to the penalty spot but his decision was overturned following a VAR review.
Milan showed more attacking intent after the interval but created few clear chances with strikes from Brahim Diaz and Junior Messias missing the target and Sandro Tonali hitting the post.
Substitute Tommaso Pobega also had a late opportunity to pull a goal back for Milan but goalkeeper Andre Onana kept out his low effort from the edge of the penalty area.
"The lads played with their hearts and heads, covering every part of the pitch," Inter coach Simone Inzaghi said. "We're happy, but we're still missing a piece."
It was the first time Inter have beaten their neighbours in a European knockout tie, with Milan progressing from both previous meetings, most recently in the 2004-05 Champions League quarter-finals.
That was a stormy game and when Inter had a goal disallowed in the second leg, their fans reacted angrily and a flare thrown on to the pitch struck Milan goalkeeper Dida. The match was abandoned with Milan leading 1-0.
Milan were awarded a 3-0 win, having won the first leg 2-0, and went on to lose a dramatic final to Liverpool on penalties.
Inter host Milan in the second leg at the same venue on Tuesday and the winners will face Real Madrid or Manchester City in the final.