Leicester edged Brighton on penalties to reach the Carabao Cup quarter-finals after an entertaining game finished 2-2 at the King Power Stadium.
Neal Maupay's penalty hit the crossbar and Enock Mwepu's effort was saved by Danny Ward to send the Foxes through.
Harvey Barnes had opened the scoring early on before a dramatic end to the first half saw two goals in added time.
Adam Webster poked in but Ademola Lookman put the Foxes back in front, before Mwepu levelled again on 71.
It was the midfielder's first goal for the Seagulls, as he looped a header into the corner - but the celebrations turned to disappointment after penalties.
Maupay was the first to miss from the spot, hammering his effort against the bar, before Ward got down smartly to save Mwepu's low kick and book Leicester a spot in the last eight.
"When you get to this stage you want to get to the quarter-finals," said Leicester boss Brendan Rodgers, who made 10 changes to his side.
"I am delighted with the mentality of the team, a lot of players who haven't played as much, we showed our quality to get the goals and composure at the end to go through."
A minute's silence took place before kick-off to mark the third anniversary of a helicopter crash that killed Foxes chairman Vichai Srivaddhanaprabh.
The draw for the quarter-finals will take place on Saturday.