Brighton have not reached the quarter final of the competition since the 1978-79 season, coming agonisingly close last night after playing out an entertaining 2-2 draw to precede the shootout.
Lapses in defensive organisation and failure to provide that elusive clinical edge proved Brighton's pitfall once more, and the side have now gone five matches without victory in all competitions.
Regardless, the Seagulls enjoyed a cup run that saw two trips to Wales and an enthralling contest where two exciting Premier League outfits put on an emphatic show.
Changes were made; a wealth of players usually outside the starting 11 were offered the chance to demonstrate their worth and they took it with aplomb.
Brighton won 2-0 at the Principality Stadium, with their rotated lineup dictating possession and standing firm in defence as Cardiff attempted to muster some offensive drive.
After travelling to face Cardiff, Brighton were then pitted against further Welsh opposition, though this time the contest was waged on home soil.
The sides each fielded rotated lineups and produced an entertaining and competitive match, with Swansea particularly impressing with intense, cohesive pressing and chipping at the Brighton defence with fluid forward movements.
But promising young forward Aaron Connolly served as talisman as Swansea's energy levels somewhat withered as the match went on, and swiftly scored twice before half-time to conclude the affair.
Playing 45 minutes, the touted Tariq Lamptey continued his recovery from a detrimental hamstring injury that had kept him sidelined since December 2020 and looked composed in his role.
Signed from Chelsea, Lamptey has caught the attentions of fans and pundits alike after an excellent start to life on the south coast and will no doubt galvanise his teammates as he continues to push for regular minutes.
Make no mistake, Leicester are hitting their groove.
The Foxes are a team with an abundance of quality in all areas of the pitch, and have an FA Cup trophy and two Europa League campaigns to show for it across the past two years.
Now unbeaten in five, Leicester are on course to challenge for silverware once more but were made to work for victory against Potter's side, who might just have clinched the win had it not been for uncharacteristic defensive mistakes.
Brighton maintained a flowing game and attempted to slice City apart with incisive movements, a compliment to Potter's managerial ability and tactical prowess.
The sides could not be separated after 90 minutes of gripping action, both had demonstrated their offensive pedigree, and Albion might just have prevailed had individual errors not played a defining role in both of Leicester's strikes.
Changes had been made, rotation was necessary.
A daunting trip to Anfield imminently awaits Brighton and by starting key individuals such as Yves Bissouma, Marc Cucurella, and captain Lewis Dunk from the bench, the prospect of defeating Liverpool in successive meetings will have been weakened.