Kelechi Iheanacho scored a 94th-minute winner as Leicester edged past Brighton to reach the FA Cup quarter-finals.
Substitute Iheanacho nodded in from Youri Tielemans’ cross to settle an otherwise unremarkable contest.
With both sides making seven changes for the tie, the first half was a slow burner and neither team were able to register a single shot on target.
The second half improved slightly with Andi Zeqiri and Cengiz Under both having efforts ruled out for offside. The quarter-final draw takes place on Thursday, with matches being played across the weekend of 20-21 March.
Brendan Rodgers’ side, now beaten just once in 13 games, reached the last eight of the competition for the second successive season — and will be boosted by news that a nasty-looking knee injury to James Justin is not as bad as was first feared.
The in-form English full-back landed awkwardly in the second half and seemed to jar his leg on impact with the turf. He was carried off on a stretcher.
Rodgers said: “Hopefully it’s not as bad as what it first seemed. He said he could have walked off and after five minutes in the changing room it eased up. On first look there’s nothing major, which is good news.”
The two best openings of a lacklustre 45 minutes fell to Adam Lallana but the Brighton midfielder was unable to work goalkeeper Danny Ward with either of his strikes from outside the area.
The lively Zeqiri curled wide and had a low shot kept out by Leicester’s second-choice keeper Ward. At the other end Turkey international Under’s effort, following a lovely one-two with James Maddison, was pushed away by Christian Walton.
With the prospect of extra time and penalties looming on a chilly evening, the Foxes played a quick corner deep in injury time and Iheanacho popped up to nod home his fifth of the season.
Leicester boss Brendan Rodgers: “I believe we have improved. The mentality in the team has grown over the past year. Let’s see if we can make the next step; let’s see who we get.
“Everyone was delighted it wasn’t half hour more for extra time. The game was a bit broken and there weren’t so many chances. You have to keep going and keep fighting. It’s another clean sheet, a great win, players getting minutes and getting through to the quarter-finals again.”
Brighton manager Graham Potter: “We’re disappointed; we put such a lot into the game. There were some tired minds on the pitch and we switched off a little bit. Our performance was really good; we more than matched them. We’re happy about that but disappointed with the result.”
