The Lions conceded the opening four goals, seized control then withstood a final-quarter fightback, further demoralising the same opposition they crushed by 10 goals in the 2024 grand final.
Isaac Heeney's late goal put the match in the balance with 63 seconds remaining, but Brisbane stood up in a frantic finish to prevail 12.14 (86) to 12.10 (82).
Starcevich, who suffered a concussion in a pre-season game, was helped off the field in Saturday's fourth term after an accidental clash of heads with Sydney's Justin McInerney.
Perennially underrated forward Zac Bailey was arguably best on ground, kicking four goals in the absence of late scratching Charlie Cameron (tight calf).
Cameron's omission and the first-term substitution of livewire Kai Lohmann, who suffered an apparent ankle injury, forced Chris Fagan to rework plans for a new-look forward line and the void left by retired talisman Joe Daniher.
At times it looked highly unlikely the Lions would kick a winning score.
But Bailey stepped up, while Dayne Zorko and Logan Morris also produced goals in the third term that were worthy of any highlight reel.
Ruck Oscar McInerney, last year's hard-luck story after suffering a shoulder injury in the Lions' preliminary final, Jarrod Berry, Josh Dunkley and debutant Levi Ashcroft were also influential for the visitors.
Dual Brownlow medallist Lachie Neale failed to touch the ball in either the second or third quarters as tagger James Jordon curbed his influence.
The Swans threw the kitchen sink at the reigning premiers in a game that, because of multiple turnovers, errors and questionable decision-making, often felt like the antithesis of a grand final.
That is to be expected from any fixture in mid-March, let alone one played in the hottest part of an unseasonably warm day in which the temperature in some parts of Sydney hit 38C.
Sydney stars Chad Warner and Nick Blakey were among the Swans guilty of uncharacteristic mistakes and dropped marks, while the Lions were likewise rusty and fumbly at key junctures.
But, if measured by the result being in the balance for as long as possible, it was a far more exciting spectacle than the clubs' previous meeting.
Swans coach Dean Cox moved down to the boundary line during the game, in an effort to rally his side that is now 0-2 and faces Fremantle in Perth next week.
A poor turnover from Matt Roberts, whose kick in defence picked out Lions gun Dunkley and gifted the visitors a decisive goal in the arm-wrestle of a final term, was particularly costly.
