Whilst there was technically nothing to play for in these sides’ meeting just four days prior, Inter’s commanding 3-0 victory at this very same venue will no doubt have given them the morale advantage ahead of this showpiece.
And aside from some rash challenges early on, the Serie A champions looked comfortable in their dominance before taking a deserved lead on 14 minutes.
Federico Dimarco’s corner took a glancing touch off Marcus Thuram at the near post, causing it to cannon off Adam Marusic’s head and into the net.
Missing manager Maurizio Sarri from the touchline but roared on by a de facto home crowd - who had been absent in protest at the club’s hierarchy for much of this season – Lazio sought to respond, but were repeatedly stifled before they could even get past midfield.
And that relentless Inter press was instrumental in a cruel second, coming when Nuno Tavares was pickpocketed on the right by Denzel Dumfries, who kept his cool and slid a pass across the face of goal for Lautaro Martínez to tap home.
Lazio looked deflated for the remainder of the half, but were fired up after the restart and nearly hit back when Tijjani Noslin hit just wide.
Inter were just as promising on the counter, with Luis Henrique somehow ballooning wide having been picked out by Dimarco, before Piotr Zieliński sliced past the post from the edge of the area.
Boulaye Dia did call Josep Martínez into action in an attempt to force a nervy conclusion, but the Spanish stopper dealt with the danger and set his side up to see out a comfortable win.
Inter became the first side to win both Serie A and the Coppa Italia in a single season since Juventus in 2017/18, turning their remaining two matches into a figurative lap of honour after a successful first season in charge for Cristian Chivu.
Meanwhile, Lazio came up short in their only remaining opportunity to qualify for European football next season and will now be focused on avoiding a first bottom-half league finish in 16 years.
Flashscore Man of the Match: Federico Dimarco (Inter)