Inter Milan striker Romelu Lukaku struck an 82nd-minute penalty as they won impressively 2-0 at Champions League opponents Benfica.
Nicolo Barella's header had put Inter in the lead in the quarterfinal first leg in Lisbon.
Inter were superb defensively over the night as Benfica struggled to get a foothold into the game.
Rafa Silva was denied by Andre Onana's first-half save before Inter fullback Denzel Dumfries produced a crucial block from close range after Barella had put the visitors ahead.
Inter wrapped up the win when substitute Lukaku, on loan from Chelsea, scored from the spot after former Inter player Joao Mario was judged to have handled the ball by VAR.
Inter will be confident of reaching the semifinals with the second-leg to be held at home at San Siro stadium on April 19.
