Hull's David Meyler with decisive penalty as Tigers advance to cup quarter-finals
Hull City 1 Leicester City 1 (Hull City win 5-4 on penalties)
Hull reached the League Cup quarter-finals for the first time in their history after overcoming Barclays Premier League high-fliers Leicester on penalties.
The Tigers needed a shoot-out to see off Accrington at the first hurdle and 11 weeks on Steve Bruce's men stepped up to the spot once again to keep their run in the competition going.
Back-up goalkeeper Eldin Jakupovic was the hero, denying Riyad Mahrez - whose extra-time goal had been cancelled out by Abel Hernandez - and leaving David Meyler to strike home the decisive spot-kick against a much-changed Leicester.
The hosts, too, made a string of changes and dominated the match for large parts, with Greg Luer, Ryan Taylor and Mo Diame coming close before tempers frayed when Harry Maguire's header was adjudged not to have crossed the line.
Things became even more heated soon after extra-time got under way as offside appeals against Jamie Vardy were ignored, allowing fellow substitute Mahrez to slot home.
Anger quickly turned to relief, though, thanks to Hull's own replacements, with Hernandez turning home after Chuba Akpom's effort was saved to take the match to penalties.
City goalkeeper Jakupovic saved the first spot-kick and Claudio Ranieri's men never got back on terms, with Meyler striking the penalty that secured a 5-4 triumph.
There were vast changes across the line-ups for this last-16 tie, which started with Andrej Kramaric - one of Leicester's 10 alterations - coming close from distance,
It proved one of few chances for the visitors as Hull dominated the first half, with Ritchie de Laet's block preventing Luer from ending a lovely team move with an early goal.
Shaun Maloney sent an acrobatic attempt into the side-netting as the home side bossed the play, albeit without creating many clear-cut chances.
Diame almost made up for a wild, ballooned effort with a fizzing strike after half-time, before providing a cross to the back post, where Taylor's header rippled the side-netting.
Vardy was brought on in the 65th minute in a bid to sharpen Leicester's blunt attack and Bruce responded with attacking changes of his own in the form of Akpom and Hernandez.
However, it was the hosts' centre-back Maguire that looked to have made a late breakthrough as Schwarzer fumbled the defender's shot, only for the assistant to rule the ball had not crossed the line.
It was a controversial moment that would have mattered little had Hernandez beaten the veteran Australian minutes later, although the visitors threatened most towards the end of second half.
Mahrez, Vardy and Danny Drinkwater had effort blocked before stoppage-time made way for extra-time, which started with Akpom being booked for diving.
The decision infuriated Hull players and fans alike - anger that increased when an offside shout against Vardy was ignored and his shot was pushed into the path of Mahrez to slot home.
Andy Robertson was booked for his apoplectic remonstrations, but this tie was far from over as Akpom got behind the Leicester back line and Schwarzer parried his shot into the path of Hernandez to bundle home.
Marc Albrighton came close soon after, but it was Hull that looked most likely to score, with Yohan Benaloune almost diverting a Hernandez cross past Schwarzer, whose goal was being peppered by hopeful efforts.
However, there was to be no separating the sides and the match went to penalties, where Jakupovic's save from Mahrez proved the difference.