Brighton secured a place in the knockout stages of the Europa League after Joao Pedro’s second-half penalty earned an unconvincing 1-0 victory away to 10-man AEK Athens.
In-form forward Pedro converted his fifth goal of the competition in the 55th minute to guarantee the Seagulls a top-two finish in Group B.
Albion were second best before the VAR-awarded spot-kick and fortunate not to fall behind in the closing stages of the first half when AEK forward Steven Zuber struck a post.
The lively hosts were forced to play the final 25 minutes a man down following Mijat Gacinovic’s dismissal for a second yellow card.
Roberto De Zerbi’s men will vie for first place in the pool – and automatic qualification for the last 16 – when Marseille visit the Amex Stadium in the final round of fixtures in two weeks’ time.
Brighton’s maiden European campaign was launched with an underwhelming 3-2 defeat to the Greek champions in September.
Yet the Premier League club arrived at the AEK Arena in control of their own destiny thanks to a battling comeback draw in Marseille and back-to-back wins over Ajax.
Head coach De Zerbi made four changes from Saturday’s 3-2 success at Nottingham Forest, including recalling match-winner Pedro, and saw his injury-hit side start in the ascendancy.
Evan Ferguson was twice blocked as he threatened inside two minutes, while AEK defender Domagoj Vida came close to a calamitous own goal with a firm back pass which had goalkeeper Cican Stankovic scampering across his line.
But the disjointed Seagulls faded from the encouraging start and were in regular danger of falling behind.
AEK forward Zuber forced Albion keeper Bart Verbruggen to turn over a powerful drive before heading narrowly wide from the resultant corner.
Brighton were then lucky not to concede just before the break amid relentless home pressure.
Switzerland international Zuber worked space inside the 18-yard box with quick feet before seeing his angled drive deflect off Lewis Dunk and rattle the left post, with Gacinovic unable to head home the rebound.
Verbruggen was forced to save from Gacinovic after the restart before Brighton snatched the lead against the run of play during a pivotal spell in the contest.
Swiss referee Sandro Scharer initially waved play on when Pedro went to ground under pressure from AEK captain Damian Szymanski before pointing to the spot after viewing a replay of the incident on the pitch-side monitor.
Brazilian forward Pedro duly dispatched his sixth penalty of the season – and third against AEK – by sending Stankovic the wrong way from 12 yards to back up his weekend brace at Forest as a substitute.
Brighton had barely threatened before the opener and their cause was further strengthened just 10 minutes later when Serbia midfielder Gacinovic over-ran the ball and raked his studs into Joel Veltman to receive a second booking.
Seagulls striker Ferguson threatened to double the lead before being repelled as he tried to round Stankovic having been sent clear.
AEK midfielder Orbelin Pineda then flashed wide as the home side pushed for a leveller but Brighton, despite an uninspiring display, held on relatively comfortably to ensure their European adventure continues.