Match ends, Burton Albion 1, Leicester City 3.
James Maddison's late goal sealed Leicester's passage into the quarter-finals of the Carabao Cup at League One Burton.
Despite making nine changes from the record-equalling win at Southampton, Brendan Rodgers' team were fluent throughout.
Goals from Kelechi Iheanacho and Youri Tielemans put the visitors in charge.
And Maddison's close-range effort secured the win after Liam Boyce scored with a 20-yard drive for the hosts.
Until then, last season's semi-finalists Burton, who have already knocked out Premier League Bournemouth this term, had shown they were capable of springing another surprise.
That was largely due to a mistake from Foxes keeper Danny Ward, who mishandled Boyce's rasping effort, coupled with the form of goalkeeper Kieran O'Hara.
But the on-loan Manchester United player could do little to prevent any of the visitors' goals - with Iheanacho sweeping his effort into the left corner from Tielemans' cross, the Belgian finding the bottom corner from Dennis Praet's cut-back and Maddison flicking in Demarai Gray's near-post cross.
The draw for the quarter-finals will be at 08:45 GMT on Thursday and will be broadcast live on The Zoe Ball Breakfast Show on BBC Radio 2. You can also follow it on the BBC Sport website.
Relentless Leicester advance
Leicester made the short journey up the M1 motorway looking to maintain their fine run of form and, despite making a raft of changes, emerged as worthy winners.
On a night when the likes of Jamie Vardy, Harvey Barnes and Maddison all started on the bench, Rodgers will surely be satisfied by the relentless approach his team employed.
Rodgers' side have now won six of their last seven matches in all competitions and Gray, Tielemans and Hamza Choudhury set the tone for a performance that was brimming with energy and drive.
Gray initiated both of his side's first-half goals with incisive first-time passing that carved open the hosts down either flank.
And Tielemans again demonstrated his value as an attacking force - the 22-year-old having now provided more assists than any other Foxes player since his debut in February.
Those contributions played a significant role in the three-time winners of the competition progressing to the last eight stage for the third successive season.
Burton manager Nigel Clough: "They had chances all through the game with the quality they have. We think their starting 11 was worth £100m so it's very difficult when you have that quality against you and you give them a goal in the first few minutes.
"I thought we gave them a game, especially in the second half. We had situations all throughout the game. We couldn't quite finish ours, we got a goal back and made it interesting for 30 minutes or so."
Leicester City assistant manager Chris Davies: "You saw the strength of the squad tonight and the performance was good. We did it at Luton in the previous round, we changed it for that game as well.
"We've not done it just to give them a bit of game-time, we've done it because we trust them. We know they've got the quality to deliver the performance and the result for us.
"We're into the quarter-finals again and we'll be looking forward to that game when it comes around. There's a lot of belief at the moment and the confidence is really high."
- 15HutchinsonSubstituted forDyerat 45'minutes
- 4EdwardsSubstituted forSbarraat 88'minutes
- 17SarkicSubstituted forTempletonat 88'minutes
- 20ChoudhurySubstituted forNdidiat 88'minutes
- 26PraetSubstituted forMaddisonat 83'minutes
- 14IheanachoSubstituted forBarnesat 66'minutes
- 21Ricardo Pereira
- Darren England
- Shots on Target
Second Half ends, Burton Albion 1, Leicester City 3.
Corner, Leicester City. Conceded by John-Joe O'Toole.
James Maddison (Leicester City) wins a free kick in the attacking half.
Foul by Scott Fraser (Burton Albion).
Attempt blocked. Demarai Gray (Leicester City) left footed shot from the centre of the box is blocked. Assisted by Harvey Barnes.
Attempt missed. Harvey Barnes (Leicester City) right footed shot from the centre of the box is too high.
Goal! Burton Albion 1, Leicester City 3. James Maddison (Leicester City) right footed shot from the centre of the box to the bottom left corner. Assisted by Demarai Gray.
Substitution, Burton Albion. Joe Sbarra replaces Ryan Edwards.
Substitution, Burton Albion. David Templeton replaces Oliver Sarkic.
Substitution, Leicester City. Wilfred Ndidi replaces Hamza Choudhury.
James Maddison (Leicester City) wins a free kick in the defensive half.
Foul by Ryan Edwards (Burton Albion).
Attempt blocked. Ryan Edwards (Burton Albion) right footed shot from outside the box is blocked. Assisted by Nathan Broadhead.
Attempt missed. Youri Tielemans (Leicester City) right footed shot from outside the box misses to the left following a corner.
Corner, Leicester City. Conceded by Lloyd Dyer.
Attempt missed. Oliver Sarkic (Burton Albion) right footed shot from the right side of the box is just a bit too high. Assisted by Scott Fraser.
Attempt missed. Ryan Edwards (Burton Albion) right footed shot from outside the box misses to the left.
Substitution, Leicester City. James Maddison replaces Dennis Praet.
Offside, Leicester City. James Justin tries a through ball, but Demarai Gray is caught offside.