Lazio set up Coppa Italia final with Inter after penalty shootout triumph against Atalanta
The teams faced off again seven weeks on from their opening 2-2 stalemate at the Stadio Olimpico, as La Dea looked to end a streak of only two successes in their prior 10 fixtures over every tournament ahead of this meeting.
In spite of that dismal streak, Raffaele Palladino's squad started with vigour and controlled the opening moves in Bergamo.
High quality openings proved rare, however, the most promising arriving as Nicola Zalewski's effort was turned aside when Charles De Ketelaere nodded down Lorenzo Bernasconi's delivery into the penalty area.
Lazio offered scant danger of their own, managing just one significant moment when Toma Bašić sent a header comfortably above the crossbar off Mattia Zaccagni's set piece.
Considering the importance involved, it came as little shock that the pair registered a mere single attempt on target combined by the interval.
Atalanta stayed the stronger candidates to open the scoring, and suffered a disputed disallowance of a goal shortly beyond the 60th minute.
Éderson finished from near range, though a VAR check ruled that Edoardo Motta had both hands holding the ball when Nikola Krstović located the Brazilian.
This proved a vital escape for the Biancocelesti, who might have yielded a spot kick earlier if Mario Gila faced punishment for handling.
Lazio saw their own handball claim against Giorgio Scalvini rejected prior to Tijjani Noslin's left footed effort missing the mark, with the Dutch forward then denied by a block from Mario Pašalić.
Nevertheless, the away team netted what seemed the key strike of the contest as Alessio Romagnoli slotted home a fine left footed volley from Zaccagni's corner.
Yet Pašalić equalised just two minutes afterwards when Krstović fed the Croatian, who unleashed a deflected finish beyond Motta.
Lazio's number one then pulled off a superb stop to tip Gianluca Scamacca's headed attempt against the woodwork, forcing the compelling tie into extra time.
Atalanta appeared on course for the Italian capital when Giacomo Raspadori nodded the home side ahead in the 96th minute, only for an offside decision on Davide Zappacosta during the move to see the effort cancelled out.
Little action unfolded across the tentative extra half hour, paving the way for a high tension penalty shootout.
Motta emerged as the hero in the shootout, delivering a masterclass by saving four spot kicks consecutively against Nuno Tavares, Scamacca, Pašalić and De Ketelaere, guiding Maurizio Sarri's side into the final.
The Biancocelesti now seek an eighth triumph in this tournament, their initial one since the 2018/19 season, in the matchup with the Nerazzurri on 13 May.