Seagulls eagerly awaited European bow fell flat during Brighton vs AEK Athens stunned Roberto de Zerbi's men with a 3-2 Europa League group stage victory.
The Seagulls twice pegged AEK back after Djibril Sidibe and Mijat Gacinovic had taken advantage of Lewis Dunk's absence through injury to score from first-half set pieces.
But, even with 13 minutes' injury-time, Brighton had no answer after substitute Ezequiel Ponce converted a third after 84 minutes.
Niclas Eliasson was given too much time to cross after Tariq Lamptey had slipped as AEK launched a speedy counter-attack, Ponce applying the finish.
It meant Joao Pedro's unique double ended up counting for nothing.
Evidently, it is not unusual for the video assistant referee to intervene to award penalties. Remarkably, this time it happened twice, on both occasions after the former Watford forward had gone down – he was booked for diving the first time.
Brighton's £30 million record signing took both penalties, twice sending the goalkeeper the wrong way.
Just before the teams came out, the stadium announcer called on the Brighton fans to "drink it in".
It is barely 25 years since the club were nearly relegated from the Football League, in the final match ever to be played at their beloved Goldstone Ground.
Where the club has advanced to is remarkable.
Thanks to the vision of owner Tony Bloom, who was watching from the stands, they have a superb stadium, a state-of-the-art training ground and one of the most attractive and progressive teams in the Premier League.
Now they have Europe, with the mouth-watering visit of former Champions League winners Ajax to come next month and Marseille to follow in December.
Chief executive Paul Barber is fond of saying Brighton are looking forward, not back but, despite the disappointment of defeat on the night, if ever there was a night for nostalgia, this was it.
Images of the past were played across the stadium – more, it felt, as a thank you to the fans who stood with the club in those dark days and are now getting their reward.
Sadly for Brighton, one of the key components in their rise from the Championship to the brink of the top four was missing during Brighton vs AEK Athens.
Dunk must have known, like everyone else, that AEK's two first-half goals were avoidable and had he been on the pitch rather than in the dug-out, Brighton would have had a far better chance of avoiding them.
Igor Julio was not solely at fault but the sight of the Brazilian, a £14.5m signing last summer, getting booked for dragging back Levi Garcia just inside the Brighton half as he feared the Trinidad and Tobago international was about the run away from him was further evidence of what Dunk's absence meant.
On his full debut, on-loan Barcelona star Ansu Fati – whose last European appearance was against Manchester United in this competition last year – drew an excellent first-half save out of Cican Stankovic.
When the game was still there for Brighton to win, Joao Pedro disappointed in not completing his hat-trick after beating the offside trap and running clear but firing his shot straight at Stankovic.
Pascal Gross had Brighton's best opportunity to level for a third time but again, the AEK keeper was equal to the challenge.